After releasing the awesome OS X Lion Apple has released lot of updates and things following it to support it and to makes its use more simple and easy,
Lot of issues could appear in this time need to be fixed one of them was The instillation alert issue it was a difficult process when you install Xcode 4.1 you had to quit iTunes if it was running and even when you did that the alert didn’t appear and let you don’t know whats exactly happening,Apple has fixed this issue by realeasing the Xcode 4.1.1 update to fix iTunes instillation alert according to Apple release note :
What’s New in Version 4.1.1
This is a delta update to Install Xcode.app that fixes the “Installation Alert” to quit iTunes. You do not need to re-run the installer if you already have Xcode 4.1 for Lion successfully installed, as the included tools are unchanged in this update.
its available now for free in Mac App Store.