With Debian amd64, and C::B rev 8248.
I also tried to do that through windows (with xming) as it gaves correct results with shortcuts like SHIFT+Fxx, but the issue is the same.
I do not think it could be a configuration issue, so maybe I made something wrong on my system? (Not installed a gtk library, by example, but it sounds strange to me that everything else works fine - except the SHIFT+Fxx, but if I remember correctly it was already discussed that this is a Xorg conf issue - )