TB Mail Download - Always D/loads old messages

Hi people this is my first post here. I've been using portable apps for a couple of months now. I use them mainly on my PC because it's superior to installing software. I keep them on a seperate partition so when my C: partition gets screwed or reverted to a backup I don't lose and settings, favourites or addresses etc and I need only to recreate shortcuts. Portable apps rocks! I use the FF, TB, OP, NVU, Gaim and abiword!

I got a problem with TB though. Before using the portable app I used the normal intalling version and this behaved correctly. Under the Server Settings for my account I check the box "Leave messages on server for at most 90 days", this ensure that I always have a backup of my email remotely. But on this version of TB it does leave the messages on the server but everytime it checks for new email it downloads them again. Filling my inbox up with repeats. As I said the install version (0.9 i think) behanved correctly. Is this a quirk with the portable version or am I missing something?

Cheers, keep up the excellent work on development, I can't wait for a portable image app - personally I recommend FastStone Image Viewer.

Gabe