Weird bug when I get interrupted casting a spell

[pridefc1]

Any time a mob interrupts me while casting a spell, I get bugged so I can't cast ANY spell and have to /Reload.
Pain in the ass to do this mid fight and causes problems, anyone else have this?

[Razash]

I get this as well. It happens with or without addons. Anybody know how to fix it?

[Razash]

Nobody else gets this error?

[Resolve]

havent had the pleasure to be interrupted while casting..

[Razash]

Well I don't know about the OP but this also happens to me if I cast+move or esc to cancel spell.