u guys doing all of this through activesync ? if so do this, click on activsync via ppc, click menu, configure server, next, next, highlight email, and click settings, then download the past should be "all". i believe this is what you gotta do in order to keep your emails. if i think of the other option i will fill you guys in.
this is from when i had issues
http://forum.ppcgeeks.com/showthread.php?t=3779