I'm aware of the problem. It's related to texture units not being properly allocated, though I haven't managed to figure out just how that happens, yet. (Mainly because I'm actually having quite a hard time reproducing the problem. I know it happens in the presence of smoke, but it happens far from every time.)
You may be able to work around the problem by using the console command ":gl progmode a", which tells the client to always use progammed shader mode, rather than only when it's strictly necessary to do so. That isn't quite supported, however, and has a few problems on its own, but they are lesser problems than the icons not drawing at all. To switch back, use ":gl progmode r".