1) Activate open SSH and connect to your iPhone
2) Go to /<root>/system/library/Carrier Bundles/O2_UK.bundle/
3) Upload and replace the modified file 'carrier.plist' to the directory.
4) Restart your iPhone.

Remember you do it at your own risk!

I have included the Original 'old' file if the fix go's wrong!

NOTE,Remove 'old' from the file name when replacing!