diff --git a/build.lua b/build.lua
index 319571d8a..b0c2beebd 100644
--- a/build.lua
+++ b/build.lua
@@ -12,6 +12,7 @@ vars.plats = {
 	"linuxppc",
 	"linuxmips",
 	"msdos86",
+	"msdos386",
 	"osx386",
 	"osxppc",
 	"pc86",
diff --git a/plat/msdos/include/ack/plat.h b/plat/msdos/include/ack/plat.h
new file mode 100644
index 000000000..4343f1cf8
--- /dev/null
+++ b/plat/msdos/include/ack/plat.h
@@ -0,0 +1,11 @@
+/* $Source$
+ * $State$
+ * $Revision$
+ */
+
+#ifndef _ACK_PLAT_H
+#define _ACK_PLAT_H
+
+#define ACKCONF_WANT_O_TEXT_O_BINARY 1
+
+#endif
diff --git a/plat/msdos/include/build.lua b/plat/msdos/include/build.lua
new file mode 100644
index 000000000..6ae480041
--- /dev/null
+++ b/plat/msdos/include/build.lua
@@ -0,0 +1,24 @@
+include("plat/build.lua")
+
+headermap = {}
+packagemap = {}
+
+local function addheader(h)
+	headermap[h] = "./"..h
+	packagemap["$(PLATIND)/msdos86/include/"..h] = "./"..h
+end
+
+addheader("ack/plat.h")
+addheader("sys/types.h")
+
+acklibrary {
+	name = "headers",
+	hdrs = headermap
+}
+
+installable {
+	name = "pkg",
+	map = packagemap
+}
+
+
diff --git a/plat/msdos/include/sys/types.h b/plat/msdos/include/sys/types.h
new file mode 100644
index 000000000..005f48eb0
--- /dev/null
+++ b/plat/msdos/include/sys/types.h
@@ -0,0 +1,9 @@
+#ifndef _SYS_TYPES_H
+#define _SYS_TYPES_H
+
+typedef long pid_t;
+typedef int mode_t;
+typedef long time_t;
+typedef long suseconds_t;
+
+#endif
diff --git a/plat/msdos86/libsys/brk.c b/plat/msdos/libsys/brk.c
similarity index 100%
rename from plat/msdos86/libsys/brk.c
rename to plat/msdos/libsys/brk.c
diff --git a/plat/msdos/libsys/build.lua b/plat/msdos/libsys/build.lua
new file mode 100644
index 000000000..d808fe894
--- /dev/null
+++ b/plat/msdos/libsys/build.lua
@@ -0,0 +1,28 @@
+bundle {
+	name = "srcs",
+	srcs = {
+		"./creat.c",
+		"./gettimeofday.c",
+		"./kill.c",
+		"./lseek.c",
+		"./open.c",
+		"./read.c",
+		"./setmode.c",
+		"./signal.c",
+		"./sys_fdmodes.c",
+		"./sys_getmode.c",
+		"./sys_initmain.c",
+		"./sys_iseof.c",
+		"./sys_seteof.c",
+		"./sys_seterrno.c",
+		"./sys_setmode.c",
+		"./write.c",
+	}
+}
+
+bundle {
+	name = "headers",
+	srcs = {
+		"./libsys.h"
+	}
+}
diff --git a/plat/msdos86/libsys/creat.c b/plat/msdos/libsys/creat.c
similarity index 100%
rename from plat/msdos86/libsys/creat.c
rename to plat/msdos/libsys/creat.c
diff --git a/plat/msdos86/libsys/gettimeofday.c b/plat/msdos/libsys/gettimeofday.c
similarity index 100%
rename from plat/msdos86/libsys/gettimeofday.c
rename to plat/msdos/libsys/gettimeofday.c
diff --git a/plat/msdos86/libsys/kill.c b/plat/msdos/libsys/kill.c
similarity index 100%
rename from plat/msdos86/libsys/kill.c
rename to plat/msdos/libsys/kill.c
diff --git a/plat/msdos86/libsys/libsys.h b/plat/msdos/libsys/libsys.h
similarity index 100%
rename from plat/msdos86/libsys/libsys.h
rename to plat/msdos/libsys/libsys.h
diff --git a/plat/msdos86/libsys/lseek.c b/plat/msdos/libsys/lseek.c
similarity index 100%
rename from plat/msdos86/libsys/lseek.c
rename to plat/msdos/libsys/lseek.c
diff --git a/plat/msdos86/libsys/open.c b/plat/msdos/libsys/open.c
similarity index 100%
rename from plat/msdos86/libsys/open.c
rename to plat/msdos/libsys/open.c
diff --git a/plat/msdos86/libsys/read.c b/plat/msdos/libsys/read.c
similarity index 100%
rename from plat/msdos86/libsys/read.c
rename to plat/msdos/libsys/read.c
diff --git a/plat/msdos86/libsys/setmode.c b/plat/msdos/libsys/setmode.c
similarity index 100%
rename from plat/msdos86/libsys/setmode.c
rename to plat/msdos/libsys/setmode.c
diff --git a/plat/msdos86/libsys/signal.c b/plat/msdos/libsys/signal.c
similarity index 100%
rename from plat/msdos86/libsys/signal.c
rename to plat/msdos/libsys/signal.c
diff --git a/plat/msdos86/libsys/sys_fdmodes.c b/plat/msdos/libsys/sys_fdmodes.c
similarity index 100%
rename from plat/msdos86/libsys/sys_fdmodes.c
rename to plat/msdos/libsys/sys_fdmodes.c
diff --git a/plat/msdos86/libsys/sys_getmode.c b/plat/msdos/libsys/sys_getmode.c
similarity index 100%
rename from plat/msdos86/libsys/sys_getmode.c
rename to plat/msdos/libsys/sys_getmode.c
diff --git a/plat/msdos86/libsys/sys_initmain.c b/plat/msdos/libsys/sys_initmain.c
similarity index 100%
rename from plat/msdos86/libsys/sys_initmain.c
rename to plat/msdos/libsys/sys_initmain.c
diff --git a/plat/msdos86/libsys/sys_iseof.c b/plat/msdos/libsys/sys_iseof.c
similarity index 100%
rename from plat/msdos86/libsys/sys_iseof.c
rename to plat/msdos/libsys/sys_iseof.c
diff --git a/plat/msdos86/libsys/sys_seteof.c b/plat/msdos/libsys/sys_seteof.c
similarity index 100%
rename from plat/msdos86/libsys/sys_seteof.c
rename to plat/msdos/libsys/sys_seteof.c
diff --git a/plat/msdos86/libsys/sys_seterrno.c b/plat/msdos/libsys/sys_seterrno.c
similarity index 100%
rename from plat/msdos86/libsys/sys_seterrno.c
rename to plat/msdos/libsys/sys_seterrno.c
diff --git a/plat/msdos86/libsys/sys_setmode.c b/plat/msdos/libsys/sys_setmode.c
similarity index 100%
rename from plat/msdos86/libsys/sys_setmode.c
rename to plat/msdos/libsys/sys_setmode.c
diff --git a/plat/msdos86/libsys/write.c b/plat/msdos/libsys/write.c
similarity index 100%
rename from plat/msdos86/libsys/write.c
rename to plat/msdos/libsys/write.c
diff --git a/plat/msdos386/boot.s b/plat/msdos386/boot.s
new file mode 100644
index 000000000..451291b13
--- /dev/null
+++ b/plat/msdos386/boot.s
@@ -0,0 +1,170 @@
+#
+! $Source$
+! $State$
+! $Revision$
+
+! Declare segments (the order is important).
+
+.sect .text
+.sect .rom
+.sect .data
+.sect .bss
+
+.sect .text
+.use16
+
+#define STACK_BUFFER 128 /* number of bytes to leave for stack */
+
+begtext:
+	! Make sure we are running under MS-DOS 2 or above.
+	!
+	! While at it, also remember the actual DOS version, so that we know
+	! whether DOS gives us the program's name in the environment
+	! segment.  (DOS 3+ does; DOS 2.x does not.)
+	movb ah, 0x30
+	int 0x21
+	cbw
+	cmpb al, 2
+	xchg bp, ax
+	jnc ok_sys
+
+	mov dx, bad_sys_msg
+dos_msg:
+	movb ah, 9
+	int 0x21
+	ret
+
+ok_sys:
+	! Resize the program's memory control block (MCB) to cover only the
+	! program's near code and data space.  Use the starting sp value as
+	! a guide to how much memory we can grab.  Abort on any failure.
+	!
+	! As a side effect, this also frees up any memory allocated to our
+	! program beyond 64 KiB.  (The freed memory can possibly be used by
+	! e.g. child processes, in the future.)
+	!
+	! Also check that we have some space between the BSS end and the
+	! starting sp.
+	cmp sp, endbss+STACK_BUFFER
+	jb no_room
+
+	movb ah, 0x4a
+	mov bx, sp
+	movb cl, 4
+	shr bx, cl
+	inc bx
+	int 0x21
+	jc no_room
+
+	! Clear BSS.
+	mov di, begbss
+	mov cx, endbss+1
+	sub cx, di
+	shr cx, 1
+	xor ax, ax
+	cld
+	rep stosw
+
+	! Get the size of the environment variables plus (if present) the
+	! program name.  Also count the number of environment variables.
+	xor di, di
+	mov es, 0x002C(di)
+	! ax = 0 from above
+	cwd				! dx = count of env. vars.
+	! cx = 0 from above
+	dec cx				! cx = max. str. bytes to scan
+	scasb				! handle special case of empty env.
+	jz is_empty_env
+size_env:
+	inc dx
+	repnz scasb
+	scasb
+	jnz size_env
+is_empty_env:
+	cmp bp, 2
+	jz no_argv0
+	scasw
+	repnz scasb
+no_argv0:
+
+	! Copy out the environment variables and (possibly) program name
+	! onto the stack.
+	mov si, di
+	dec si
+	std
+copy_env:
+	and si, -2
+	eseg lodsw
+	push ax
+	jnz copy_env
+	mov cx, sp
+
+	! Reset DF and es properly.
+	cld
+	push ss
+	pop es
+
+	! Reserve space for argc and the argv and envp pointers on the
+	! stack.  These will be passed to __m_a_i_n later.
+	sub sp, 6
+	mov ax, sp
+
+	! Build up argc, argv[], and envp[].
+	push ax				! output buffer for argc, argv, envp
+	push bp				! MS-DOS version
+	push cx				! env. string data
+	push dx				! count of env. vars.
+	mov ax, 0x0080
+	push ax				! raw command line
+	call __sys_initmain
+	add sp, 10
+
+	! Bail out if something went wrong.
+	test ax, ax
+	jnz no_room
+
+	! argc, argv, and envp are now at the stack top.  Now go.
+	call __m_a_i_n
+	add sp, 6
+	push ax
+	call _exit
+
+no_room:
+	mov dx, no_room_msg
+	call dos_msg
+	movb al, -1
+	jmp al_exit
+
+	! Exit.
+.define __exit
+.extern __exit
+.define EXIT
+.extern EXIT
+__exit:
+EXIT:
+	pop bx
+	pop ax
+al_exit:
+	movb ah, 0x4c
+	int 0x21
+
+! Define symbols at the beginning of our various segments, so that we can find
+! them. (Except .text, which has already been done.)
+
+.define begtext, begdata, begbss
+.sect .data;       begdata:
+.sect .rom;        begrom:
+.sect .bss;        begbss:
+
+.sect .rom
+
+! Some text messages.
+bad_sys_msg: .ascii 'Bad DOS$'
+no_room_msg: .ascii 'No room$'
+
+! Some magic data. All EM systems need these.
+
+.define .trppc, .ignmask, _errno
+.comm .trppc, 4
+.comm .ignmask, 4
+.comm _errno, 4
diff --git a/plat/msdos386/build-pkg.lua b/plat/msdos386/build-pkg.lua
new file mode 100644
index 000000000..98cce47cc
--- /dev/null
+++ b/plat/msdos386/build-pkg.lua
@@ -0,0 +1,25 @@
+include("plat/build.lua")
+
+ackfile {
+	name = "boot",
+	srcs = { "./boot.s" },
+	vars = { plat = "msdos386" }
+}
+
+build_plat_libs {
+	name = "libs",
+	arch = "i386",
+	plat = "msdos386",
+}
+
+installable {
+	name = "pkg",
+	map = {
+		"+tools",
+		"+libs",
+        "./include+pkg",
+		["$(PLATIND)/msdos386/boot.o"] = "+boot",
+        ["$(PLATIND)/msdos386/libsys.a"] = "./libsys+lib",
+	}
+}
+
diff --git a/plat/msdos386/build-tools.lua b/plat/msdos386/build-tools.lua
new file mode 100644
index 000000000..d28aee904
--- /dev/null
+++ b/plat/msdos386/build-tools.lua
@@ -0,0 +1,21 @@
+include("plat/build.lua")
+
+build_as {
+	name = "as",
+	arch = "i386",
+}
+
+build_ncg {
+	name = "ncg",
+	arch = "i386",
+}
+
+return installable {
+	name = "tools",
+	map = {
+		["$(PLATDEP)/msdos386/as"] = "+as",
+		["$(PLATDEP)/msdos386/ncg"] = "+ncg",
+		["$(PLATIND)/descr/msdos386"] = "./descr",
+		"util/opt+pkg",
+	}
+}
diff --git a/plat/msdos386/descr b/plat/msdos386/descr
new file mode 100644
index 000000000..f6559471e
--- /dev/null
+++ b/plat/msdos386/descr
@@ -0,0 +1,77 @@
+var w=4
+var wa=2
+var p=4
+var pa=2
+var s=2
+var sa=2
+var l=4
+var la=2
+var f=4
+var fa=2
+var d=8
+var da=2
+var x=8
+var xa=2
+var ARCH=i386
+var PLATFORM=msdos386
+var PLATFORMDIR={EM}/share/ack/{PLATFORM}
+var CPP_F=-D__MSDOS__ -D__DOS__ -D_DOS
+var ALIGN=-a0:2 -a1:2 -a2:2 -a3:2
+var MACHOPT_F=-m8
+var EGO_PLAT_FLAGS=-M{EM}/share/ack/ego/{ARCH}.descr
+
+# Override the setting in fe so that files compiled for this platform can see
+# the platform-specific headers.
+
+var C_INCLUDES=-I{PLATFORMDIR}/include -I{EM}/share/ack/include/ansi
+
+name be
+	from .m.g
+	to .s
+	program {EM}/lib/ack/{PLATFORM}/ncg
+	args <
+	stdout
+	need .e
+end
+name as
+	from .s.so
+	to .o
+	program {EM}/lib/ack/{PLATFORM}/as
+	args - -o > <
+	prep cond
+end
+name led
+	from .o.a
+	to .out
+	program {EM}/lib/ack/em_led
+	mapflag -l* LNAME={PLATFORMDIR}/lib*
+	mapflag -fp FLOATS={EM}/{ILIB}fp
+	args {ALIGN} {SEPID} \
+		({RTS}:.b=-u _i_main) \
+	    (.e:{HEAD}={PLATFORMDIR}/boot.o) \
+		({RTS}:.ocm.bas.b={PLATFORMDIR}/c-ansi.o) \
+		({RTS}:.c={PLATFORMDIR}/c-ansi.o) \
+		({RTS}:.mod={PLATFORMDIR}/modula2.o) \
+		({RTS}:.p={PLATFORMDIR}/pascal.o) \
+		-o > < \
+		(.p:{TAIL}={PLATFORMDIR}/libpascal.a) \
+		(.b:{TAIL}={PLATFORMDIR}/libb.a) \
+		(.bas:{TAIL}={PLATFORMDIR}/libbasic.a) \
+		(.mod:{TAIL}={PLATFORMDIR}/libmodula2.a) \
+		(.ocm:{TAIL}={PLATFORMDIR}/liboccam.a) \
+		(.ocm.bas.mod.b.c.p:{TAIL}={PLATFORMDIR}/libc.a) \
+		{FLOATS?} \
+		(.e:{TAIL}={PLATFORMDIR}/libem.a \
+		           {PLATFORMDIR}/libsys.a \
+		           {PLATFORMDIR}/libc.a \
+		           {PLATFORMDIR}/libem.a \
+		           {PLATFORMDIR}/libend.a)
+	linker
+end
+name cv
+	from .out
+	to .exe
+	program {EM}/bin/aslod
+	args < >
+	outfile msdos386.exe
+end
diff --git a/plat/msdos386/include/ack/plat.h b/plat/msdos386/include/ack/plat.h
new file mode 100644
index 000000000..c0d1b9fff
--- /dev/null
+++ b/plat/msdos386/include/ack/plat.h
@@ -0,0 +1,6 @@
+#ifndef _ACK_PLAT_H
+#define _ACK_PLAT_H
+
+#define ACKCONF_WANT_O_TEXT_O_BINARY 1
+
+#endif
diff --git a/plat/msdos386/include/build.lua b/plat/msdos386/include/build.lua
new file mode 100644
index 000000000..693abd0c1
--- /dev/null
+++ b/plat/msdos386/include/build.lua
@@ -0,0 +1,24 @@
+include("plat/build.lua")
+
+headermap = {}
+packagemap = {}
+
+local function addheader(h)
+	headermap[h] = "./"..h
+	packagemap["$(PLATIND)/msdos386/include/"..h] = "./"..h
+end
+
+addheader("ack/plat.h")
+addheader("sys/types.h")
+
+acklibrary {
+	name = "headers",
+	hdrs = headermap
+}
+
+installable {
+	name = "pkg",
+	map = packagemap
+}
+
+
diff --git a/plat/msdos386/include/sys/types.h b/plat/msdos386/include/sys/types.h
new file mode 100644
index 000000000..005f48eb0
--- /dev/null
+++ b/plat/msdos386/include/sys/types.h
@@ -0,0 +1,9 @@
+#ifndef _SYS_TYPES_H
+#define _SYS_TYPES_H
+
+typedef long pid_t;
+typedef int mode_t;
+typedef long time_t;
+typedef long suseconds_t;
+
+#endif
diff --git a/plat/msdos386/libsys/build.lua b/plat/msdos386/libsys/build.lua
new file mode 100644
index 000000000..c2ae13f52
--- /dev/null
+++ b/plat/msdos386/libsys/build.lua
@@ -0,0 +1,47 @@
+acklibrary {
+    name = "lib",
+    srcs = {
+--		"./brk.c",
+--		"./close.s",
+--		"./creat.c",
+--		"./errno.s",
+--		"./getpid.s",
+--		"./gettimeofday.c",
+--		"./_hol0.s",
+--		"./isatty.s",
+--		"./kill.c",
+--		"./lseek.c",
+--		"./open.c",
+--		"./read.c",
+--		"./setmode.c",
+--		"./signal.c",
+--		"./sys_exists.s",
+--		"./sys_fdmodes.c",
+--		"./sys_getdate.s",
+--		"./sys_getmode.c",
+--		"./sys_gettime.s",
+--		"./sys_initmain.c",
+--		"./sys_iseof.c",
+--		"./sys_isopen.s",
+--		"./sys_isreadyr.s",
+--		"./sys_rawcreat.s",
+--		"./sys_rawlseek.s",
+--		"./sys_rawopen.s",
+--		"./sys_rawrw.s",
+--		"./sys_seteof.c",
+--		"./sys_seterrno.c",
+--		"./sys_setmode.c",
+--		"./sys_xret.s",
+--		"./unlink.s",
+		"plat/msdos/libsys+srcs",
+    },
+	deps = {
+		"lang/cem/libcc.ansi/headers+headers",
+		"plat/msdos386/include+headers",
+		"plat/msdos/libsys+headers",
+	},
+    vars = {
+        plat = "msdos386"
+    }
+}
+
diff --git a/plat/msdos86/libsys/build.lua b/plat/msdos86/libsys/build.lua
index eddbbf262..e7d9b8fc7 100644
--- a/plat/msdos86/libsys/build.lua
+++ b/plat/msdos86/libsys/build.lua
@@ -1,43 +1,28 @@
 acklibrary {
     name = "lib",
     srcs = {
-		"./brk.c",
 		"./close.s",
-		"./creat.c",
 		"./errno.s",
 		"./getpid.s",
-		"./gettimeofday.c",
 		"./_hol0.s",
 		"./isatty.s",
-		"./kill.c",
-		"./lseek.c",
-		"./open.c",
-		"./read.c",
-		"./setmode.c",
-		"./signal.c",
 		"./sys_exists.s",
-		"./sys_fdmodes.c",
 		"./sys_getdate.s",
-		"./sys_getmode.c",
 		"./sys_gettime.s",
-		"./sys_initmain.c",
-		"./sys_iseof.c",
 		"./sys_isopen.s",
 		"./sys_isreadyr.s",
 		"./sys_rawcreat.s",
 		"./sys_rawlseek.s",
 		"./sys_rawopen.s",
 		"./sys_rawrw.s",
-		"./sys_seteof.c",
-		"./sys_seterrno.c",
-		"./sys_setmode.c",
 		"./sys_xret.s",
 		"./unlink.s",
-		"./write.c",
+		"plat/msdos/libsys+srcs",
     },
 	deps = {
 		"lang/cem/libcc.ansi/headers+headers",
 		"plat/msdos86/include+headers",
+		"plat/msdos/libsys+headers",
 	},
     vars = {
         plat = "msdos86"