I pretty much always use Firefox with the ZWC and I've never seen this issue, but I'm posting on behalf of my many IE users. When in the "Compose Message" window, whether typing a new message or replying to a message, it sometimes does not allow you to select any text. Let's say I am typing a new message and a type a sentence but decide it's worded wrong, or I just don't need it, or whatever. Click at the beginning of the sentence and then trying to drag the mouse over the text to select it, but nothing happens. A couple of users have shown me examples of this issue, and I've just been testing with IE and had it happen to me. I thought it was an HTML-mode vs Text-mode issue, but that does not appear to be the case; it just happened to me while in Text mode. Note, this issue doesn't happen all the time, and at least at this point I haven't figure out what triggers it.
Anyone else experiencing the same thing?