Sorry to tell you, unless you are running a rooting phone, using a ROM that allows apps2sd, you are stuck with the internal memory. How many apps to you have installed? Go to "settings-sd card and internal storage" and it should show you how much internal memory you have left. All apps and their memory is stored on internal memory. The sd card only stores pictures, music, and misc. stuff that apps put there. I've ran into this problem before and the only way to get around it was to uninstall some apps and make more room. This should be fixed with 2.2 as it will have apps2sd built into the system.