broken modules

Hi

How do I tell if a module is broken? As in:

http://not.toms.net/twiki/bin/view/Tomsrtbt/BrokenModules

If I do:

# insmod ppp.o

I get:

Using ppp.o
insmod: unresolved symbol slhc_init
insmod: unresolved symbol slhc_free
insmod: unresolved symbol slhc_uncompress
insmod: unresolved symbol slhc_toss
insmod: unresolved symbol slhc_remember
insmod: unresolved symbol slhc_compress

Does that mean that the module is broken or that it depends on somethingelse?

TIA

Pete