I'm wondering if this is possible:

In my lab, we're not allowed to chat using any messenger or the sort. Now, if you are chatting with someone using MSN Messenger, you can see the window for it in the taskbar. (and you'll get in trouble)

I'm wondering if it's possible to change that little green icon thingy to something more 'work-related' such as the default windows icon, or anything else for that matter?

Any ideas for this at all? Much appreciated.