I recently upgraded my router to c2900-universalk9_npe-mz.SPA.151-2.T1.bin to support SRST 8.0. I upgraded so my 6921 phones would be supported in SRST. After upgrading I couldn't place any outbound calls, but I could receive calls. Using the CSIM start command from the router, I can dial any external number. Can anyone help here, according to prior IOS release notes, this issue should've been resolved.