diff --git a/src/system/libroot/posix/arch/x86/Jamfile b/src/system/libroot/posix/arch/x86/Jamfile
index 921a3e0676..a2e1d411e9 100644
--- a/src/system/libroot/posix/arch/x86/Jamfile
+++ b/src/system/libroot/posix/arch/x86/Jamfile
@@ -1,7 +1,7 @@
 SubDir HAIKU_TOP src system libroot posix arch x86 ;
 
 KernelMergeObject posix_arch_$(TARGET_ARCH).o :
-	setjmp.c
+	setjmp.S
 	setjmp_save_sigs.c
 	sigsetjmp.S
 	siglongjmp.S
diff --git a/src/system/libroot/posix/arch/x86/setjmp.S b/src/system/libroot/posix/arch/x86/setjmp.S
new file mode 100644
index 0000000000..7ca9a69eef
--- /dev/null
+++ b/src/system/libroot/posix/arch/x86/setjmp.S
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2004-2005, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "setjmp_internal.h"
+
+
+/* int setjmp(jmp_buf buffer) */
+FUNCTION(setjmp):
+	pop		%eax		// pop argument and return pointer from stack
+	pop		%ecx
+	pushl	$0			// push new argument (for saveMask) and old stuff
+	push	%ecx		// back onto the stack
+	push	%eax
+	jmp		__sigsetjmp	// let sigsetjmp() do the actual work
+
+#pragma weak _setjmp=setjmp
+
diff --git a/src/system/libroot/posix/arch/x86/setjmp.c b/src/system/libroot/posix/arch/x86/setjmp.c
deleted file mode 100644
index 789748335c..0000000000
--- a/src/system/libroot/posix/arch/x86/setjmp.c
+++ /dev/null
@@ -1,20 +0,0 @@
-/*
- * Copyright 2004-2005, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
- * Distributed under the terms of the MIT License.
- */
-
-
-#include <setjmp.h>
-
-#ifdef COMPILE_FOR_R5
-#	undef setjmp
-#endif
-
-
-int
-setjmp(jmp_buf buffer)
-{
-	return sigsetjmp(buffer, 0);
-}
-
-#pragma weak _setjmp = setjmp
diff --git a/src/system/libroot/posix/arch/x86/siglongjmp.S b/src/system/libroot/posix/arch/x86/siglongjmp.S
index 3e3819495a..7774e61327 100644
--- a/src/system/libroot/posix/arch/x86/siglongjmp.S
+++ b/src/system/libroot/posix/arch/x86/siglongjmp.S
@@ -16,8 +16,8 @@
 FUNCTION(siglongjmp):
 FUNCTION(longjmp):
 FUNCTION(_longjmp):
-	mov		4(%esp,1), %ecx
-	mov		8(%esp,1), %eax
+	mov		4(%esp), %ecx
+	mov		8(%esp), %eax
 
 	// restore registers
 	mov		JMP_REGS_EBX(%ecx), %ebx
diff --git a/src/system/libroot/posix/arch/x86/sigsetjmp.S b/src/system/libroot/posix/arch/x86/sigsetjmp.S
index fa8cd4ae4f..cd91fe4c1c 100644
--- a/src/system/libroot/posix/arch/x86/sigsetjmp.S
+++ b/src/system/libroot/posix/arch/x86/sigsetjmp.S
@@ -1,7 +1,7 @@
-/* 
-** Copyright 2004, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
-** Distributed under the terms of the Haiku License.
-*/
+/*
+ * Copyright 2004-2005, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
 
 
 #include "setjmp_internal.h"
@@ -30,7 +30,8 @@ FUNCTION(sigsetjmp):
 	// save stack and return address (because that's where we intend to jump to)
 	lea		4(%esp,1), %ecx
 	mov		%ecx, JMP_REGS_ESP(%eax)
-	mov		0(%esp,1), %ecx
+	mov		0(%esp), %ecx
 	mov		%ecx, JMP_REGS_PC(%eax)
 
 	jmp		__setjmp_save_sigs
+