Call-limit how to change/remove?

Does somebody know how to change/diseble call-limit variable added by FreePBX in
asterisk_additional.conf to each extension?

I’m not able to find this variable in FreePbx gui, but it always add
call-limit=50

It Is not possible to change it manually in sip_additional.conf, because after any changes provided via gui it always return to 50.

Please see this ticket http://www.freepbx.org/v2/ticket/2127
Why do you want to edit this setting?