I've been using the latest off the bzr, updating every couple of weeks or so. The issue has been around for quite a while. In fact, I'd've sworn I'd seen something about it in the mailing list at some point, but I couldn't find anything when I searched my gmail for something on it.
2013/2/27 David Engster <email@example.com>
Nate Schley writes:Which CEDET version are you using?
> While I'm coding in various buffers, sometimes semantic/cedet wants to delete
> some buffer(s) I'm not immediately using. The clue: A pop-up window saying
> words to the effect of
> "foo.cpp has been modified. Do you really want to kill it"