Adding misdn trunks errors

Hello to all
When trying to add a misdn trunk in the trunk page after selecting misdn as the new trunk type I got the following error below:
What can I do to help track this issue?
Thanks
Eduardo Farias
Doctrine_Record_UnknownPropertyException
freepbx/libraries/doctrine/lib/Doctrine/Record/Filter/Standard.php [55]:
Unknown record property / related component "SipInterfaceTrunk" on "MisdnTrunk"
Stack Trace
* freepbx/libraries/doctrine/lib/Doctrine/Record.php [1332]:
Doctrine_Record_Filter_Standard->filterGet( )
* freepbx/libraries/doctrine/lib/Doctrine/Record.php [1291]:
Doctrine_Record->_get( )
* freepbx/libraries/doctrine/lib/Doctrine/Access.php [72]:
Doctrine_Record->get( )
* modules/sipinterface/plugins/sipinterface.php [60]:
Doctrine_Access->__get( )
*
SipInterface_Plugin->view( )
* freepbx/helpers/plugins.php [79]:
call_user_func( )
* freepbx/helpers/plugins.php [118]:
plugins::runEvents( )
* modules/trunkmanager/controllers/trunkmanager.php [102]:
plugins::views( )
*
TrunkManager_Controller->add( )
* system/core/Kohana.php [270]:
ReflectionMethod->invokeArgs( )
*
Kohana::instance( )
* system/core/Event.php [209]:
call_user_func( )
* system/core/Bootstrap.php [55]:
Event::run( )
* index.php [106]:
require( )__________________


