urgent about regional setting

Dear All,
A listwiev brings some data from SQL server. And also post the data into the corresponding textboxes when click to the rows. But When I change to regional settings (for example Turkish regional)It again brings data but doesn't post them to the textboxes. And ther is no date/time conversions at textboxes. I programmed under English(US)regional settings with Turkish Q keyboard.I works fine. What could be your suggettion. I wanna be region independent. Thanks alot