Debug question

[Mipam]

Hi All,

Forgive me if this question is off topic, i don't know what other mailing 
list would be good for this one.
Suppose the following: I experience a hang and the system reboots.
After this i'll look in /var/crash and find a nice core file.
My swap is large enough to cover the whole memory and more so it should be 
okay. However, "gdb kernel vmcore.0" tells me that vmcore.0 is not a core 
dump.... :-(
Any hints?
Regards,

Mipam.