The wonderful people at the xda developer's site came up with a cab for installing the original "flip" clock that is on the European version of the Diamond onto Sprint's.
http://forum.xda-developers.com/showthread.php?t=420887&page=18#178Important Instructions:
Make sure you disable TouchFlo3d before installing!!! Go to all settings, personal tab, today. Under the "items" tab uncheck TouchFlo 3d on the bottom of the scroll-down list. If your phone does a strange visual thing where you can only see half the screen after this, restart the phone.
Now that Touchflo 3d is disabled you should be able to go to the start menu, finder, and install the cab. After it is done, click ok to restart the phone. When the phone restarts, enable TouchFlo 3d again by checking back that box mentioned above. Finally, do a Soft Reset to avoid any issues (I had a phone call... sound volume seemed to go back down to a level before I did the call volume registry tweak. A soft reset took care of the issue.)
Also: The yellow icon next to the word "Sprint" above the clock will not be there anymore.
If you want to uninstall to get back to the original Sprint clock, disable TouchFlo 3d first.
I have this on my phone, and love it! No issues so far.