Since someone always ends up asking when they have an issue...
link to community forum thread @ Shaw
Apparently lines are down completely or will only work for some numbers. For example, I can call any landline right now, but if I try to call my husband's cell phone, or my own, or any other cell phone in the Calgary area, a recording comes on saying the number is not in service. I am able to reach another cell using my cell phone. Shaw has no ETA on when this will be fixed.
At first I thought it was limited to cell numbers whose carrier is Telus, but I've tried a variety of cell numbers with different carriers - Virgin, Rogers, Bell - and cannot get through, unless they are out of the Calgary calling area/are not a Calgary number.
Just thought I'd post a heads up. 911 service is not affected apparently.