iTunes doesn't find iPhoto library

iTunes doesn't find iPhoto Libray. This happens every time I do any kind of change to my iPhoto Library.

Thw problem prevents me to:

• view photos on Apple TV
  • the options in iTunes (Advanced-menu - Select pictures to share) are grey / not available
  • Apple TV tells me to turn on sharing, but sharing is on
• sync photos to iPad

  iTunes shows a messasge saying it can't find the iPhoto Library

I have tried:

• repair permissions (iPhoto)
• rebuild database (iPhoto)

I did find a workaround, but no permanent sollution. The workaround is:

• Open iPhoto and quit iPhoto again without doing anything that might affect the library
• Go to iTunes and everything is ok, except that i sometimes need to sync all pictures again to the iPad, also the ones that are allready there, because iTunes believes the iPad has been synced previously to another library...

This (anoying) workaround seems to work every time, but sure isn't a good sollution.

Why can't my iTunes stick the the iPhoto Library?

Or - what happens to my iPhoto Library every time I make a change, resulting in iTunes not finding the library?

Any suggestions?