diff --git a/mach/m68k4/libem/inn.s b/mach/m68k4/libem/inn.s
index 2bc4c6e08..ef0176274 100644
--- a/mach/m68k4/libem/inn.s
+++ b/mach/m68k4/libem/inn.s
@@ -18,8 +18,11 @@
 	asr.l	#3,d2
 	cmp.l	d0,d2
 	bcc	1f
+	bclr	#0,d2
+	bclr	#1,d2
 	add.l	d2,a0
-	btst	d1,(a0)
+	move.l	(a0),d2
+	btst	d1,d2
 	beq	1f
 	move.l	#1,d0
 	bra	2f
diff --git a/mach/m68k4/libem/set.s b/mach/m68k4/libem/set.s
index 7a9287726..f413311b3 100644
--- a/mach/m68k4/libem/set.s
+++ b/mach/m68k4/libem/set.s
@@ -24,6 +24,10 @@
 	move.w	#ESET,-(sp)
 	jsr	.trp
 1:
+	bclr	#0,d2
+	bclr	#1,d2
 	add.l	d2,a1
-	bset	d1,(a1)
+	clr.l	d2
+	bset	d1,d2
+	move.l	d2,(a1)
 	jmp	(a0)