diff --git a/mach/6500/cg/mach.h b/mach/6500/cg/mach.h
index 1adf66775..d8068ad60 100644
--- a/mach/6500/cg/mach.h
+++ b/mach/6500/cg/mach.h
@@ -10,7 +10,7 @@
 
 #define cst_fmt         "%d"
 #define off_fmt         "%d"
-#define ilb_fmt         "I%03x%x"
+#define ilb_fmt         "I%x_%x"
 #define dlb_fmt         "_%d"
 #define hol_fmt         "hol%d"
 
diff --git a/mach/i86/cg/mach.h b/mach/i86/cg/mach.h
index 8410ca9a5..ec3b070ed 100644
--- a/mach/i86/cg/mach.h
+++ b/mach/i86/cg/mach.h
@@ -12,7 +12,7 @@
 
 #define cst_fmt         "%d"
 #define off_fmt         "%d"
-#define ilb_fmt         "I%03x%x"
+#define ilb_fmt         "I%x_%x"
 #define dlb_fmt         "_%d"
 #define hol_fmt         "hol%d"
 
diff --git a/mach/m68k2/cg/mach.h b/mach/m68k2/cg/mach.h
index 8a385ffb8..521cb1ae7 100644
--- a/mach/m68k2/cg/mach.h
+++ b/mach/m68k2/cg/mach.h
@@ -9,7 +9,7 @@
 #define	pop_fmt		"(sp)+"
 #define cst_fmt		"%ld"
 #define	off_fmt		"%ld"
-#define ilb_fmt		"I%03x%x"
+#define ilb_fmt		"I%x_%x"
 #define dlb_fmt		"_%d"
 #define	hol_fmt		"hol%d"
 
diff --git a/mach/ns/ncg/mach.h b/mach/ns/ncg/mach.h
index 225c9dcd5..cdb6ff5d5 100644
--- a/mach/ns/ncg/mach.h
+++ b/mach/ns/ncg/mach.h
@@ -1,4 +1,4 @@
-/* $Header$ */
+$Header$ */
 
 #define ex_ap(y)        fprintf(codefile,".extern %s\n",y)
 #define in_ap(y)        /* nothing */
@@ -10,7 +10,7 @@
 
 #define cst_fmt         "%ld"
 #define off_fmt         "%ld"
-#define ilb_fmt         "I%03x%x"
+#define ilb_fmt         "I%x_%x"
 #define dlb_fmt         "_%d"
 #define hol_fmt         "hol%d"