I Photo says it is damaged and needs to be reinstalled

I did all the things described in the articles found in this forum (removing the app, removing any Preferences from /Volumes/User/Users/chris/Library/Preferences, removing receipts from /private/var/db/receipts (I am using Max OS 10.7.4 - Lion) ...). After that I reinstalled iPhoto from my iLife '11 DVD. Finally it installed fine, but when I start it it says that some software actualization is required. The software update dialog appears, search for updates, but does not find anything iPhoto related. Starting iPhoto always brings up this dialog - so I am not able to start it...

WHAT TO DO ?