diff -r 0ffb4e86fcc9 -r a179b74831c9 kernel/eka/memmodel/epoc/flexible/mmu/mcodepaging.cpp
--- a/kernel/eka/memmodel/epoc/flexible/mmu/mcodepaging.cpp	Thu Jul 15 20:11:42 2010 +0300
+++ b/kernel/eka/memmodel/epoc/flexible/mmu/mcodepaging.cpp	Thu Aug 19 11:14:22 2010 +0300
@@ -131,6 +131,8 @@
 			{
 			TRACEB(("DCodePagedMemoryManager::InstallPagingDevice drive=%d",i));
 			TAny* null = 0;
+			if(aDevice->iType & DPagingDevice::EMediaExtension)
+				__e32_atomic_store_ord_ptr(&iDevice[i], null);
 			if(!__e32_atomic_cas_ord_ptr(&iDevice[i], &null, aDevice)) // set iDevice[i]=aDevice if it was originally 0
 				{
 				// paging device already registered...