Tax Filing Software

I need a tax application very much like: [login to view URL] and [login to view URL];SP=10023&CID=0&PID=860899&PN=1&V1=860899&CUR=840&DSP=&PGRP=0&ABCODE=&CACHE_ID=0 Must support federal and state taxes as well as efiling and printing. Must be able to save tax document for future use. Should work on Vista and XP at a minimum. Need a working demo within 2 weeks and a final product delivered within 3 weeks. Must be able to provide periodic builds (this is actually going to be an open source project - you are really just jump starting the project). A link will be provided to your company in the credits page. This should be a full featured app - why can go over exact details when the project is started. Must have a decent UI. Thanks.