If you haven't already, install A-GPS and make sure the cache data is valid. When you start up Maemo Mapper, instead of seeing 0 of 0 satellites, it should say something like seeing 0 of 9-12 satellites. A-GPS will let Maemo Mapper know what to look for, which generally results in getting a faster lock.

For the quickest fix time, make sure you have a clear view of the sky (preferably towards the equator)