Bug with forking to "Trunk"

Hello all.
I’ve got bug after upgrade from 1.2.5 to 1.2.11
In my office I’ve asterisk wich connected to PSTN via Cisco 5350.
In extensions.conf I made such string:

exten => 1234,n,Dial(SIP/user&SIP/TrunkName/${mob})

in sip.conf I’ve of cause specified “user” and “Trunkname”.

On 1.2.5 everything were perfect, but after upgrade * don’t send “cancel” to Trunk when my SIPphone (aka SIP/user) place call.

Any ideas?