Calls hang in RING and DOWN state

I was using 1.4 and now I am using 1.8, I had a script on 1.4 to cut calls at 2hrs, I changed it to work on 1.8, but on 1.8 I noticed I get a lot of the following :

SIP/1xxxxxxx-0 default 20121899638 1 Down AppDial (Outgoing Line) 20121899638 762:14:0 1399775991 (None) SIP/xxxxxxxxx default

SIPxxxxxxxxxxxx default 008801817672877 1 Ringing AppDial (Outgoing Line) 008801817672877 102:24:3

As you can see above calls are stuck in Down and Ringing state for a long time, is this a bug ? Did I miss something here ?