enable debugging in kernel

[Nicolò Chieffo]

Hello. I'm experiencing a kernel bug after suspend.
I tried to boot in single user mode, without the "quiet" option, but I
cannot obtain any more specific kernel message about the error.

So I downloaded linux-image-debug-2.6.20-5-generic but I don't know
how to use it, since it shops vmlinux and not vmlinuz, so grub refuses
to boot it. How can I do?