I work for a small (barely 2 digit people) open source shop and we don't have it that way, but that's probably because we're so small...

Funnily enough I release some of my work under BSD-style licenses while company stuff is all GPL :D

[2 sidenotes though: 1) I'm in the EU, and 2) a previous job, working on the very exact same open source project, had a clause like that.]