diff --git a/mach/sun2/libsys/LIST b/mach/sun2/libsys/LIST
index 36c42ddfc..3b1529014 100644
--- a/mach/sun2/libsys/LIST
+++ b/mach/sun2/libsys/LIST
@@ -126,6 +126,7 @@ times.c
 truncate.s
 umask.s
 unlink.s
+umount.s
 unmount.s
 utime.c
 utimes.s
diff --git a/mach/sun2/libsys/umount.s b/mach/sun2/libsys/umount.s
new file mode 100644
index 000000000..f323fa5f4
--- /dev/null
+++ b/mach/sun2/libsys/umount.s
@@ -0,0 +1,4 @@
+#include "syscall.h"
+.sect .text; .sect .rom; .sect .data; .sect .bss; .sect .text
+.define _umount
+_umount: SYSTEM(SYS_umount)
diff --git a/mach/sun2/libsys/unmount.s b/mach/sun2/libsys/unmount.s
index f323fa5f4..d58bf8371 100644
--- a/mach/sun2/libsys/unmount.s
+++ b/mach/sun2/libsys/unmount.s
@@ -1,4 +1,4 @@
 #include "syscall.h"
 .sect .text; .sect .rom; .sect .data; .sect .bss; .sect .text
-.define _umount
-_umount: SYSTEM(SYS_umount)
+.define _unmount
+_unmount: SYSTEM(SYS_umount)
diff --git a/mach/sun3/libsys/LIST b/mach/sun3/libsys/LIST
index 2b746292f..cffcb20de 100644
--- a/mach/sun3/libsys/LIST
+++ b/mach/sun3/libsys/LIST
@@ -129,6 +129,7 @@ times.c
 truncate.s
 umask.s
 unlink.s
+umount.s
 unmount.s
 ustat.s
 utime.c
diff --git a/mach/sun3/libsys/sigvec.c b/mach/sun3/libsys/sigvec.c
index 82a2e69d3..9b2fb21f8 100644
--- a/mach/sun3/libsys/sigvec.c
+++ b/mach/sun3/libsys/sigvec.c
@@ -29,7 +29,7 @@ sigvec(sig,vec,ovec)
 		_sigfunc[sig] = old;
 		return -1;
 	}
-	if (ovec->handler == _sigtramp) {
+	if (ovec && ovec->handler == _sigtramp) {
 		ovec->handler = old;
 	}
 	return 0;
diff --git a/mach/sun3/libsys/umount.s b/mach/sun3/libsys/umount.s
new file mode 100644
index 000000000..f323fa5f4
--- /dev/null
+++ b/mach/sun3/libsys/umount.s
@@ -0,0 +1,4 @@
+#include "syscall.h"
+.sect .text; .sect .rom; .sect .data; .sect .bss; .sect .text
+.define _umount
+_umount: SYSTEM(SYS_umount)
diff --git a/mach/sun3/libsys/unmount.s b/mach/sun3/libsys/unmount.s
index f323fa5f4..d58bf8371 100644
--- a/mach/sun3/libsys/unmount.s
+++ b/mach/sun3/libsys/unmount.s
@@ -1,4 +1,4 @@
 #include "syscall.h"
 .sect .text; .sect .rom; .sect .data; .sect .bss; .sect .text
-.define _umount
-_umount: SYSTEM(SYS_umount)
+.define _unmount
+_unmount: SYSTEM(SYS_umount)
diff --git a/mach/vax4/libbsd4_2/LIST b/mach/vax4/libbsd4_2/LIST
index 8ea4f3315..daba62ba4 100644
--- a/mach/vax4/libbsd4_2/LIST
+++ b/mach/vax4/libbsd4_2/LIST
@@ -119,6 +119,7 @@ getrusage.s
 truncate.s
 umask.s
 umount.s
+unmount.s
 unlink.s
 utime.c
 utimes.s
diff --git a/mach/vax4/libbsd4_2/cerror.s b/mach/vax4/libbsd4_2/cerror.s
index 27af5b390..35301151a 100644
--- a/mach/vax4/libbsd4_2/cerror.s
+++ b/mach/vax4/libbsd4_2/cerror.s
@@ -1,4 +1,5 @@
-	.globl	_errno, cerror
+	.globl	_errno
+	.globl	cerror
 .comm _errno, 4
 cerror:
 	movl	r0,_errno
diff --git a/mach/vax4/libbsd4_2/unmount.s b/mach/vax4/libbsd4_2/unmount.s
new file mode 100644
index 000000000..ca040bb1e
--- /dev/null
+++ b/mach/vax4/libbsd4_2/unmount.s
@@ -0,0 +1,3 @@
+#include "syscall.h"
+DEFINE(_unmount)
+SYSTEM(SYS_umount)