I have just re-built world and kernel and get a boot failure: panic: free: guard2 fail @ 0x412f6c50 + 513 from unknown:0 --> Press a key in the console to reboot <-- I'll try to boot from a memory stick, now, but wanted to let others know, that there seems to be a problem with the latest UMA code which may cause a boot failure at this early stage. STefan