Who called from 7182100307

Received phone call on 2/15/2012
No message

Received a call today 2/23/12 - no message left  -  came in as  1-718-210-0307 (calls usually don't come in with a "1" preceding the number)

This number calls my work phone and cell phone at the same time, rings twice and hangs up...

I didn't answer the call, whihc I have been getting over the last few weeks, but a search of the Internet shows it belongs to MCI Communications.

This number has called me repeatedly. No message left. Called 2/17, 2/19, 2/22, 2/23, twice on 2/25 and again today 2/27.