Metro riders will have an even longer wait for full cell phone service in Metro tunnels.

A congressional deadline for Metro to install cell phone service in all of its tunnels was pushed back last week, from March 26 to Sept. 30.

The deadline was moved as part of Congress' latest continuing resolution, which ends Sept. 30. The deadline will have to be pushed back yet again by September, since Metro has said it can't get the work done until December 2015.

Metro is required to have the wireless service throughout the system continue receiving its annual $150 million in federal funding under a 2008 law.

Metro partnered with a group of wireless carriers to get the service installed, but the contractor for that job -- Powerwave Technologies Inc. -- filed for Chapter 11 bankruptcy protection in January and has stopped work on the project.

Powerwave said in its bankruptcy filings that the project was not profitable and that the carriers had not reimbursed it for millions of dollars in cost overruns.

The wireless carriers responded in court, saying that Powerwave wasn't maintaining the system as promised, failed to pay its subcontractors and ignored an intrusion alarm that went off in the Rosslyn Metro station.

Metro's 20 busiest stations were wired by 2009, but many tunnels between stations still do not have service.