The problem is likely becuase you compiled the module using old kernel sources. Is this a module you downloaded from the internet?
If so, make sure the symbolic link usr/src/linux points to the directory with the current kernel sources. run
ls -l /usr/src/linux
These should give you the same version number. If not, that is your problem. Change the symbolic link to point to your kernel sources (I can't remember the command line switches for that...anyone else?), and then recompile the module.
If you didn't download this module from the internet, but it was instead compiled with your kernel (or came with your distro install) do the same version check, and if they are the same do
this should recompile your modules and recopy them to the appropriate directory. Now try to load the module (use modprobe instead of insmod).