Trying to upgrade to 2.4.21-58.EL, the server had a kernel panic.

From the tech who booted the server:
QUOTE
The server was in kernel panic, this is the error that results from the new kernel.
Kernel requires old insmod, but couldn't run /bin/insmod.old: No such file or directory
ERROR: /bin/insmod exited abnormally!



CODE
root@xxx [~]# ls -l /*bin/insmod*
-rwxr-xr-x    1 root     root        13215 Oct 18  2006 /sbin/insmod*
-rwxr-xr-x    1 root     root          359 Jun 29  2004 /sbin/insmod_ksymoops_clean*
-rwxr-xr-x    1 root     root       144160 Sep 24  2004 /sbin/insmod.old*
-rwxr-xr-x    1 root     root       421752 Oct 18  2006 /sbin/insmod.static*


Any ideas on how I should proceed?