Yesterday i found myself in the same situation, here it is what i did:

WARNING: Symbol version dump /usr/src/linux-source- is missing;
modules will have no dependencies and modversions.
-> this is the main problem... you should cd to '/usr/src/linux-source-' do a 'make menuconfig' (i did it, maybe it is not neccesary) and give it a 'make' command... this will run for some time but after then you will have the Module.symvers in place...

After this i tried to compile the broadcom linux_sta, but it gave me errors... for the kernel you should download and apply a patch (same site where you can get the linux_sta driver).

I tried to compile the wl.ko module under the new kernel as well, but no luck... if anyone did it plz share your knowledge

(sorry for my poor english...)