President Barack Obama wore a White Sox cap during his ceremonial first pitch at the Washington Nationals game yesterday, but before any rabid Pale Hose supporters get too excited about it, they should know he had a bit of a problem naming any player by name. The first fan was interviewed during the game's television broadcast by former Sox pitcher Rob Dibble, who asked the president about his favorite players on the South Side growing up. This is was the point that the usually eloquent Obama began stammering. "You know uh ..... I ... I thought that ... uh .......