diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h
index 553a2584..6f62bc32 100644
--- a/arch/x86/include/asm/page.h
+++ b/arch/x86/include/asm/page.h
@@ -48,6 +48,7 @@
 #define PG_ACCESSED	(1 << _PAGE_BIT_ACCESSED)
 #define PG_DIRTY	(1 << _PAGE_BIT_DIRTY)
 #define PG_PSE		(1 << _PAGE_BIT_PSE)
+#define PG_MPE		PG_PSE
 #define PG_GLOBAL	(1 << _PAGE_BIT_GLOBAL)
 #define PG_RESERVED	(1 << _PAGE_BIT_RESERVED)
 #define PG_PAT		(1 << _PAGE_BIT_PAT)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 27294236..b79a4b60 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -113,6 +113,16 @@ static inline void write_cr3(uint32_t val) {
 	asm volatile("mov %0, %%cr3" : : "r"(val));
 }
 
+static inline uint32_t read_cr4(void) {
+	uint32_t val;
+	asm volatile("mov %%cr4, %0" : "=r"(val));
+	return val;
+}
+
+static inline void write_cr4(uint32_t val) {
+	asm volatile("mov %0, %%cr4" : : "r"(val));
+}
+
 static inline void tlb_flush_one_page(uint32_t addr)
 {
 	asm volatile("invlpg (%0)" : : "r"(addr) : "memory");
diff --git a/arch/x86/mm/page.c b/arch/x86/mm/page.c
index 114f2a66..993ccc3d 100644
--- a/arch/x86/mm/page.c
+++ b/arch/x86/mm/page.c
@@ -339,6 +339,10 @@ size_t map_region(size_t viraddr, size_t phyaddr, uint32_t npages, uint32_t flag
 
 		if (flags & MAP_NO_CACHE)
 			pgt->entries[index] |= PG_PCD;
+#ifdef CONFIG_ROCKCREEK
+		if (flags & MAP_MPE)
+			pgt->entries[index] |= PG_MPE;
+#endif
 
 		if (flags & MAP_USER_SPACE)
 			atomic_int32_inc(&task->user_usage);
@@ -684,8 +688,8 @@ int arch_paging_init(void)
 	viraddr = map_region(CRB_X0_Y0, CRB_X0_Y0, (CRB_OWN-CRB_X0_Y0+16*1024*1024)/PAGE_SIZE, MAP_KERNEL_SPACE|MAP_NO_CACHE);
 	kprintf("Map configuration registers at 0x%x\n", viraddr);
 
-	// map SCC's configuration registers
-	viraddr = map_region(MPB_X0_Y0, MPB_X0_Y0, (MPB_OWN-MPB_X0_Y0+16*1024*1024)/PAGE_SIZE, MAP_KERNEL_SPACE);
+	// map SCC's message passing buffers
+	viraddr = map_region(MPB_X0_Y0, MPB_X0_Y0, (MPB_OWN-MPB_X0_Y0+16*1024*1024)/PAGE_SIZE, MAP_KERNEL_SPACE|MAP_MPE);
 	kprintf("Map message passing buffers at 0x%x\n", viraddr);
 #endif
 
diff --git a/arch/x86/scc/scc_init.c b/arch/x86/scc/scc_init.c
index 0e3a2197..02b6057f 100644
--- a/arch/x86/scc/scc_init.c
+++ b/arch/x86/scc/scc_init.c
@@ -27,6 +27,9 @@
 
 #ifdef CONFIG_ROCKCREEK
 
+/* PSE bit for Pentium+ equals MPE (message buffer enable) flag in RCK! So, use it to create _PAGE_MPB symbol... */
+#define _CR4_MPE 0x00000800
+
 /*
  * Workaround to create a suitable argv array
  */
@@ -83,6 +86,11 @@ int scc_init(void)
 	num_ranks = RCCE_num_ues();
 	kprintf("Got rank %d of %d ranks\n", my_rank, num_ranks);
 
+	/* Enable Messagepassing in CR4 */
+	uint32_t cr4 = read_cr4();
+	cr4 = cr4 | _CR4_MPE;
+	write_cr4(cr4);
+
 	i = ReadConfigReg(CRB_OWN+GLCFG0);
 	kprintf("glcfg0 0x%x\n", i);
 
diff --git a/include/metalsvm/stdlib.h b/include/metalsvm/stdlib.h
index 6a74fac6..ca6d3d91 100644
--- a/include/metalsvm/stdlib.h
+++ b/include/metalsvm/stdlib.h
@@ -36,7 +36,9 @@ extern "C" {
 #define MAP_HEAP		(1 << 5)
 #define MAP_CODE		(1 << 6)
 #define MAP_READONLY		(1 << 7)
-
+#ifdef CONFIG_ROCKCREEK
+#define MAP_MPE			(1 << 8)
+#endif
 void NORETURN abort(void);
 void* kmalloc(size_t);
 void* mem_allocation(size_t sz, uint32_t flags);