The wireless telecommunications sector continues to buzz and now you can add the possibility of a hot initial public offering to the wave of merger activity. Sprint ( FON) and its U.K.-based partner Virgin Group are reportedly considering selling a stake in their U.S. wireless business through an IPO. Virgin Mobile, which the two companies formed as a joint venture in 2001, is talking to investment banks about the idea, according to a report in The Wall Street Journal. The companies, however, have yet to green light the IPO and are only in the proposal stage. Sprint shares closed Thursday at $24.51.