As we told you yesterday, Sprint has delayed the launch of the Treo Pro; and now our sources have told us that the actual reason is that the Treo Pro needs a bit more work, as it did not pass Sprint’s technical acceptance testing.

We have also heard whispers this morning that the new launch date for the Treo Pro on Sprint has been moved to a target date of March 15th, but that date is not set in stone.

Our sources are confirming that Sprint is not evidently confident that Palm will be able to make the necessary changes in time to meet this date. Still, Sprint wants to get it right before launch, rather than launching a phone that isn’t ready, which is good news for those waiting for the Treo Pro.

We do have it on good authority however, that they have not pulled the plug on the Treo Pro, so it would appear that it will launch at some point on Sprint.