Palm has announced that it will sell a new smart phone aimed at business users, but without the backing of a U.S. carrier.

The Treo Pro is a nice bit of kit. Slimmer and  similar in features to the Treo 800w Palm sells through Sprint Nextel will be carried in Europe by Vodafone and O2 and in Australia by Telstra.

But in the U.S. telcos have been less keen, so Palm is selling an unlocked version that's usable on AT&T Inc.'s mobile broadband network. It will cost $549 and despite the price, Palm claims it has had some significant interest from large enterprise customers.

This is because they can avoid costly international roaming fees by switching to a local carrier when traveling and businesses like that sort of thing. Like the Treo 800w, the Treo Pro runs the latest version of Microsoft Corp.'s Windows Mobile software, and has built-in Wi-Fi and GPS capabilities.