when it happens to me i just press that button, and its all back to normal
make sure you didnt edit any value for the weapon req....
if you press 1 (assuming you have a skill assigned to it) then you changed the weapon type in an attempt for it to work for other classes maybe?
or you did some bad value editing...recheck everything
as this is the first such "bug" is mentioned, and there no tut explaining how, maybe u forgot how to do it right, and edited wrong values (i know i did the first few times, even with tuts
)
all i can say is, recheck everything and make sure you didn't changed weapon type (yeh tried that, only client side, no actual damage)