A co-worker of mine was having a probelm when exporting a PDF from InDesign CS4.

Everytime he would export, regardless of his settings (Acrobat 5 and up). he was hetting a two pixel white line on the right hand side of his PDF.

When going all the way back to Acrobat 4 it went away, but the featureset in Acrobat 5 was needed.

It ended up being an issue with Acrobat itself.

In Acrobat 9, under Edit > Preferences > Page Display - Uncheck "Use 2D Graphics Acceleration."