Try removing them and see if battery drainage still occurs. The IM system (and whole Maemo system) is designed in a way that you don't need to run conversations or contacts or other apps, some deamons are just started at system startup (so when you power on your phone) and keep running in the background even if you don't need them. Knowing that you have extras-devel enabled I would try:
- removing extra protocols
- disabling extras-devel and extras-testing and leaving enabled just normal extras repository (just for a while)
- refreshing application lists from repositories
- installing extra protocols, so you will sure you have the version from Extras, not from Extras-devel. Version in Extras is tested and reported stable.
- re-enabling extras-testing and extras-devel if you really want to.

Also, don't update extra protocols support later, as it will download version from extras-devel, which may cause battery drainage (because some part of conversations runs all the time, even when you don't use Conversations application).