Recompilation of Kernel..

I tried recompiling the kernel n booting using the recompiled version.. I have a strange problem that the /proc/ksyms file gets mounted but still loading the modules gives errors like unresolved symbol...

for eg::
the symbol found in ksyms table when the properly installd kernel is run..
001169b0 register_symtab_from_R9872f07b

looks like this in the recompiled version..
00116750 register_symtab_from

Plz let me know what exactly the problem is...
This is necessary coz i wud like to make some changes in the kernel code...

Regards
Gansu.