You can also find a version in extras repository (just in case people don't want to mess with extras-devel or extras-testing).

http://maemo.org/downloads/product/M...cell-modem-ui/

Btw, for the O.P., this thread's title is a bit confusing. I first thought that you got that bill because of some kind of bug with Maemo 5. Maybe you could change it to something like "How to disable data connections" or similar. Just a suggestion