For more information on carrier settings updates, contact your carrier.
Go to your application target and go to the Build settings for that target.
I believe that you need to add VERSIONVALUE as a user-defined build setting.
In the lower-right-corner of that window, change the Based On value to "versionvalue".
For example, a friend of mine blogged about incrementing build numbers in Xcode using Plist Buddy.
Note: If you supply just the path to the plist, Plist Buddy enters interactive mode, so you can issue multiple commands before deciding to save changes.
This will correctly run the script BEFORE the Settings bundle is packaged during the build/archive process.