Seattle-based Qpass, which helps carriers sell content to cellphone subscribers, said today that it was purchased for $275 million by St. Louis-based Amdocs, a developer of customer-service software.

The purchase follows rumors circulating at CTIA Wireless 2006, the wireless association's big event in Las Vegas earlier this month.

The rumor, coming from multiple sources, was that Qpass was being purchased by Amdocs for a not-too-shabby $250 million.

The second half of the rumor was that VeriSign, which helps wireless carriers with a lot of back-end infrastructure functions, had sought Qpass as well. But according to the unverified report, VeriSign dropped out of the bidding when it purchased m-Qube, a Watertown, Mass., company that also handles transaction work for cellphone carriers, for $250 million March 20.

What a victory for Qpass, which has quite the turnaround story. The company, founded in 1997, had to ditch its public offering plans in 2000, as did many other companies. It has raised more than $100 million in financing and re-tooled its business plan more than once.

According to the press release about the sale, Amdocs will acquire all of Qpass' shares for about $275 million in cash. Through this acquisition, Amdocs can enable its customers to create additional sources of revenue through the delivery of digital goods over multiple devices and various access methods.