diff --git a/lang/mono/Makefile b/lang/mono/Makefile
index 58643c0c84b..d132f908cd8 100644
--- a/lang/mono/Makefile
+++ b/lang/mono/Makefile
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.22 2010/03/22 16:56:13 robert Exp $
+# $OpenBSD: Makefile,v 1.23 2010/03/23 08:25:26 robert Exp $
 
 # sync with net/avahi,-mono
 ONLY_FOR_ARCHS=	amd64 i386 powerpc # arm
@@ -6,7 +6,7 @@ ONLY_FOR_ARCHS=	amd64 i386 powerpc # arm
 COMMENT=	cross platform, open source .NET developement framework
 
 DISTNAME=	mono-2.6.3
-PKGNAME=	${DISTNAME}p3
+PKGNAME=	${DISTNAME}p4
 
 CATEGORIES=	lang devel
 
diff --git a/lang/mono/patches/patch-mono_mini_exceptions-amd64_c b/lang/mono/patches/patch-mono_mini_exceptions-amd64_c
new file mode 100644
index 00000000000..4de8ee24459
--- /dev/null
+++ b/lang/mono/patches/patch-mono_mini_exceptions-amd64_c
@@ -0,0 +1,105 @@
+$OpenBSD: patch-mono_mini_exceptions-amd64_c,v 1.3 2010/03/23 08:25:26 robert Exp $
+--- mono/mini/exceptions-amd64.c.orig	Tue Mar 23 08:56:35 2010
++++ mono/mini/exceptions-amd64.c	Tue Mar 23 08:59:41 2010
+@@ -711,7 +711,7 @@ mono_arch_handle_exception (void *sigctx, gpointer obj
+ 	return TRUE;
+ }
+ 
+-#ifdef MONO_ARCH_USE_SIGACTION
++#if defined(MONO_ARCH_USE_SIGACTION) && defined(UCONTEXT_GREGS)
+ static inline guint64*
+ gregs_from_ucontext (ucontext_t *ctx)
+ {
+@@ -721,7 +721,7 @@ gregs_from_ucontext (ucontext_t *ctx)
+ void
+ mono_arch_sigctx_to_monoctx (void *sigctx, MonoContext *mctx)
+ {
+-#ifdef MONO_ARCH_USE_SIGACTION
++#if defined(MONO_ARCH_USE_SIGACTION) && defined(UCONTEXT_GREGS)
+ 	ucontext_t *ctx = (ucontext_t*)sigctx;
+ 
+     guint64 *gregs = gregs_from_ucontext (ctx);
+@@ -739,6 +739,22 @@ mono_arch_sigctx_to_monoctx (void *sigctx, MonoContext
+ 	mctx->r13 = gregs [REG_R13];
+ 	mctx->r14 = gregs [REG_R14];
+ 	mctx->r15 = gregs [REG_R15];
++#elif defined(MONO_ARCH_USE_SIGACTION)
++	ucontext_t *ctx = (ucontext_t*)sigctx;
++
++	mctx->rax = UCONTEXT_REG_RAX (ctx);
++	mctx->rbx = UCONTEXT_REG_RBX (ctx);
++	mctx->rcx = UCONTEXT_REG_RCX (ctx);
++	mctx->rdx = UCONTEXT_REG_RDX (ctx);
++	mctx->rbp = UCONTEXT_REG_RBP (ctx);
++	mctx->rsp = UCONTEXT_REG_RSP (ctx);
++	mctx->rsi = UCONTEXT_REG_RSI (ctx);
++	mctx->rdi = UCONTEXT_REG_RDI (ctx);
++	mctx->rip = UCONTEXT_REG_RIP (ctx);
++	mctx->r12 = UCONTEXT_REG_R12 (ctx);
++	mctx->r13 = UCONTEXT_REG_R13 (ctx);
++	mctx->r14 = UCONTEXT_REG_R14 (ctx);
++	mctx->r15 = UCONTEXT_REG_R15 (ctx);
+ #else
+ 	MonoContext *ctx = (MonoContext *)sigctx;
+ 
+@@ -761,7 +777,7 @@ mono_arch_sigctx_to_monoctx (void *sigctx, MonoContext
+ void
+ mono_arch_monoctx_to_sigctx (MonoContext *mctx, void *sigctx)
+ {
+-#ifdef MONO_ARCH_USE_SIGACTION
++#if defined(MONO_ARCH_USE_SIGACTION) && defined(UCONTEXT_GREGS)
+ 	ucontext_t *ctx = (ucontext_t*)sigctx;
+ 
+     guint64 *gregs = gregs_from_ucontext (ctx);
+@@ -779,6 +795,22 @@ mono_arch_monoctx_to_sigctx (MonoContext *mctx, void *
+ 	gregs [REG_R13] = mctx->r13;
+ 	gregs [REG_R14] = mctx->r14;
+ 	gregs [REG_R15] = mctx->r15;
++#elif defined(MONO_ARCH_USE_SIGACTION)
++	ucontext_t *ctx = (ucontext_t*)sigctx;
++
++	UCONTEXT_REG_RAX (ctx) = mctx->rax;
++	UCONTEXT_REG_RBX (ctx) = mctx->rbx;
++	UCONTEXT_REG_RCX (ctx) = mctx->rcx;
++	UCONTEXT_REG_RDX (ctx) = mctx->rdx;
++	UCONTEXT_REG_RBP (ctx) = mctx->rbp;
++	UCONTEXT_REG_RSP (ctx) = mctx->rsp;
++	UCONTEXT_REG_RSI (ctx) = mctx->rsi;
++	UCONTEXT_REG_RDI (ctx) = mctx->rdi;
++	UCONTEXT_REG_RIP (ctx) = mctx->rip;
++	UCONTEXT_REG_R12 (ctx) = mctx->r12;
++	UCONTEXT_REG_R13 (ctx) = mctx->r13;
++	UCONTEXT_REG_R14 (ctx) = mctx->r14;
++	UCONTEXT_REG_R15 (ctx) = mctx->r15;
+ #else
+ 	MonoContext *ctx = (MonoContext *)sigctx;
+ 
+@@ -801,14 +833,16 @@ mono_arch_monoctx_to_sigctx (MonoContext *mctx, void *
+ gpointer
+ mono_arch_ip_from_context (void *sigctx)
+ {
+-	
+-#ifdef MONO_ARCH_USE_SIGACTION
+-
++#if defined(MONO_ARCH_USE_SIGACTION) && defined(UCONTEXT_GREGS)
+ 	ucontext_t *ctx = (ucontext_t*)sigctx;
+ 
+     guint64 *gregs = gregs_from_ucontext (ctx);
+ 
+ 	return (gpointer)gregs [REG_RIP];
++#elif defined(MONO_ARCH_USE_SIGACTION)
++	ucontext_t *ctx = (ucontext_t*)sigctx;
++
++	return (gpointer)UCONTEXT_REG_RIP (ctx);
+ #else
+ 	MonoContext *ctx = sigctx;
+ 	return (gpointer)ctx->rip;
+@@ -865,7 +899,7 @@ altstack_handle_and_restore (void *sigctx, gpointer ob
+ void
+ mono_arch_handle_altstack_exception (void *sigctx, gpointer fault_addr, gboolean stack_ovf)
+ {
+-#ifdef MONO_ARCH_USE_SIGACTION
++#if defined(MONO_ARCH_USE_SIGACTION) && defined(UCONTEXT_GREGS)
+ 	MonoException *exc = NULL;
+ 	ucontext_t *ctx = (ucontext_t*)sigctx;
+ 	guint64 *gregs = gregs_from_ucontext (ctx);
diff --git a/lang/mono/patches/patch-mono_mini_mini-amd64_h b/lang/mono/patches/patch-mono_mini_mini-amd64_h
new file mode 100644
index 00000000000..b1b3bc22e0c
--- /dev/null
+++ b/lang/mono/patches/patch-mono_mini_mini-amd64_h
@@ -0,0 +1,27 @@
+$OpenBSD: patch-mono_mini_mini-amd64_h,v 1.4 2010/03/23 08:25:26 robert Exp $
+--- mono/mini/mini-amd64.h.orig	Tue Mar 23 08:59:52 2010
++++ mono/mini/mini-amd64.h	Tue Mar 23 09:00:38 2010
+@@ -254,10 +254,6 @@ typedef struct {
+ 
+ #endif
+ 
+-#ifdef __OpenBSD__
+-#undef MONO_ARCH_USE_SIGACTION
+-#endif
+-
+ #endif /* PLATFORM_WIN32 */
+ 
+ #if defined (__NetBSD__)
+@@ -282,7 +278,11 @@ typedef struct {
+ 
+ #define MONO_ARCH_NOMAP32BIT
+ 
+-#elif defined (__FreeBSD__) || defined (__OpenBSD__)
++#elif defined (__OpenBSD__)
++
++#define MONO_ARCH_NOMAP32BIT
++
++#elif defined (__FreeBSD__)
+ 
+ #define REG_RAX 7
+ #define REG_RCX 4
diff --git a/lang/mono/patches/patch-mono_utils_mono-sigcontext_h b/lang/mono/patches/patch-mono_utils_mono-sigcontext_h
index f03eef9a7b8..0075a81508e 100644
--- a/lang/mono/patches/patch-mono_utils_mono-sigcontext_h
+++ b/lang/mono/patches/patch-mono_utils_mono-sigcontext_h
@@ -1,6 +1,6 @@
-$OpenBSD: patch-mono_utils_mono-sigcontext_h,v 1.1 2010/03/22 16:56:13 robert Exp $
---- mono/utils/mono-sigcontext.h.orig	Mon Mar 22 17:35:25 2010
-+++ mono/utils/mono-sigcontext.h	Mon Mar 22 17:38:49 2010
+$OpenBSD: patch-mono_utils_mono-sigcontext_h,v 1.2 2010/03/23 08:25:26 robert Exp $
+--- mono/utils/mono-sigcontext.h.orig	Fri Sep 25 16:58:11 2009
++++ mono/utils/mono-sigcontext.h	Tue Mar 23 08:56:28 2010
 @@ -54,6 +54,16 @@
  	#define UCONTEXT_REG_ESI(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_ESI])
  	#define UCONTEXT_REG_EDI(ctx) (((ucontext_t*)(ctx))->uc_mcontext.__gregs [_REG_EDI])
@@ -18,3 +18,25 @@ $OpenBSD: patch-mono_utils_mono-sigcontext_h,v 1.1 2010/03/22 16:56:13 robert Ex
  #else
  	#define UCONTEXT_REG_EAX(ctx) (((ucontext_t*)(ctx))->uc_mcontext.gregs [REG_EAX])
  	#define UCONTEXT_REG_EBX(ctx) (((ucontext_t*)(ctx))->uc_mcontext.gregs [REG_EBX])
+@@ -70,6 +80,21 @@
+ 
+ #ifdef __FreeBSD__
+ #define UCONTEXT_GREGS(ctx)	&(((ucontext_t*)(ctx))->uc_mcontext)
++#elif defined(__OpenBSD__)
++	/* OpenBSD/amd64 has no gregs array, ucontext_t == sigcontext */
++	#define UCONTEXT_REG_RAX(ctx) ((ctx)->sc_rax)
++	#define UCONTEXT_REG_RBX(ctx) ((ctx)->sc_rbx)
++	#define UCONTEXT_REG_RCX(ctx) ((ctx)->sc_rcx)
++	#define UCONTEXT_REG_RDX(ctx) ((ctx)->sc_rdx)
++	#define UCONTEXT_REG_RBP(ctx) ((ctx)->sc_rbp)
++	#define UCONTEXT_REG_RSP(ctx) ((ctx)->sc_rsp)
++	#define UCONTEXT_REG_RSI(ctx) ((ctx)->sc_rsi)
++	#define UCONTEXT_REG_RDI(ctx) ((ctx)->sc_rdi)
++	#define UCONTEXT_REG_RIP(ctx) ((ctx)->sc_rip)
++	#define UCONTEXT_REG_R12(ctx) ((ctx)->sc_r12)
++	#define UCONTEXT_REG_R13(ctx) ((ctx)->sc_r13)
++	#define UCONTEXT_REG_R14(ctx) ((ctx)->sc_r14)
++	#define UCONTEXT_REG_R15(ctx) ((ctx)->sc_r15)
+ #else
+ #define UCONTEXT_GREGS(ctx)	&(((ucontext_t*)(ctx))->uc_mcontext.gregs)
+ #endif