Volume keys in english wireless keyboard dont work

[Chiilybar]

Hi everybody,
after destroying my last german wireless keyboard i bought a new one with english characters and now the f11 and f12 keys do not work in regulating the volume up and down. I have the Mac OS X v 10.5.8
Any ideas how to fix that?
Thanks

 

[htg]

maybe you need a new driver. i don't know if this is the right one, i think its the latest one though: http://www.apple.com/downloads/macosx/apple/firmware_hardware/keyboardsoftwareupdate12.html