Palm announced an update to Windows Mobile 6 for Palm Treo 750 smartphone customers in the United States.

Windows Mobile 6 brings increased functionality, enhanced user interface and strengthened security and performance to the Treo 750 smartphone, which is offered exclusively in the United States by AT&T. The update is available as a free download for existing Treo 750 smartphone customers.

The Treo 750 currently is available in the United States on AT&T’s 3G BroadbandConnect network, which is available in more than 200 major metropolitan areas and provides average download speeds between 600Kbps (kilobits per second) and 1,400Kbps. For those customers, the update will facilitate High-speed Download Packet Access (HSDPA) capability, allowing faster data-download speeds on 3G/UMTS/HSDPA networks and access to AT&T Multimedia services: AT&T Music, CV (Video), and AT&T Mall.

“The enhanced security and productivity tools available in Windows Mobile 6 will allow people to be more productive with their Treo smartphones,” said Tim McDonough, senior director of product management at Microsoft Corp. “The Windows Mobile 6 support of storage card data encryption, combined with the ability for IT departments to wipe data remotely if a device is lost, gives businesses the confidence to use Treos to accomplish critical business tasks.”

The Treo 750 from AT&T is a five-band world phone with global 3G services that provides email, messaging, web browsing, and organizational capabilities.

“Palm and Microsoft’s alliance continues to bring the best mobile experience to Treo customers,” said Brent Remai, vice president of business and consumer marketing, Palm, Inc. “The Treo 750′s connection to Exchange Server without the need for extra servers and middleware, combined with our unique ease of use, makes the Treo a win-win solution for IT departments and business users as they seek the most of their smartphone.”