If you have linux you can format the sdcard with ext3 and then use the card for the app. Shouldn't have much to do with your phone but maybe. anyways if you don't have linux you wont be able to do it on a windows machine with standard software you'll need a third party app that can give you partitions besides windows ones. Try Gparted if you don't have a linux installation
also may want to go with a 512 meg partition
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