Digital Trends – With both AT&T and Verizon moving to LTE for 4G cell phone service it is no surprise that Sprint decided to join them. Sprint CEO Dan Hesse said Wednesday morning that the company is in talks with Clearwire to extend its contract past 2012 and use Clearwire to help power Sprintâs LTE network. News of the possible extension has caused Clearwire shares to skyrocket up nearly 20 percent.