Sprint Nextel Corp. (NYSE: S) has spent the last two years losing its valued post-paid wireless customers, even as CEO Dan Hesse has tried to stop the bleeding. Sprint has re-invented its marketing and those black and white television commercials are attention getting. But regular and business consumers are not the only users of the Sprint Nextel nationwide wireless network.

Virgin Mobile, one of the first mobile virtual network operators (MVNOs) in the U.S., is also one of the last. The virtual carrier uses Sprint Nextel's network exclusively throughout the U.S. Other MVNOs like Amp'd Mobile, ESPN Mobile and Disney Mobile have folded in the last few years, leaving Tracfone, Virgin Mobile and Net10 to pick up the slack. Even Virgin Mobile itself purchased Helio, one of the upper-tier MVNOs that also folded. With Sprint wanting as many customers -- its own or from partners like Virgin Mobile -- on its network, the struggling company recently doubled the commission to Virgin Mobile for each new subscriber it signs up.

Instead of paying Virgin Mobile $2.50 per prepaid subscriber, Sprint Nextel has been paying $4.50 per subscriber as of July 2008. The information was just released when Sprint Nextel filed documentation with the SEC, and the increased commission agreement lasts throughout 2009. Is Sprint having success using partners to sign up customers to its network, even it they are not Sprint Nextel customers?

In many ways, they are -- and Sprint Nextel has seen gains from all the customers Virgin Mobile has signed up. Sprint, who lacks a real prepaid service outside the Boost Mobile brand (which is very limited), should look into just buying Virgin Mobile and be done with it. Its larger competitors already have a complete prepaid wireless solution for those customers without stellar credit -- is Sprint ready to get serious about joining that club? It should be.