Thanks Notwerk for the link. I went through it but didn't find an answer to my problem. A kernel update ? why ? So far everything was working fine. More over I have another kernel installed (2.6.12-0.21.rdt.rhfc4.ccrma) and this one hangs as well. However on boot time the message is not "bug:soft lockup detected on cpu#0!" but "Audit (1138540964.219:0):initialized".
Very frustrating. Any ideas please to troubleshoot this problem?