Yeah, it's the same with shamans and ghost wolf. You can herb and skin while in form, but can't mine. It's really kind of annoying, but it makes mining a less desired profession unless you're using it to supply a crafting skill (someday my shammy will get his blacksmithing up...)
It is really annoying, but I don't seem them ever changing it. Biggest reason for it (I'm guessing here) is that mining actually has the whole pick-swinging animation, while none of the other gathering professions have a really noticeable animation.