I recreated the guest OS from scratch (netinst etch -> upgrade lenny) and, until now, I can still boot this kernel. So, it may have been an issue with the guest OS, not with kvm, may be bug #475923 (I was in sid and the upgrade of the console failed).
I'll do more tests tomorrow and report them here. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]