Losing leading 0's when dialing


I am using FreePBX Here in Mexico, to dial long distance or to cell phones we need to add 001, 01, 044 or 045 at the begining of the phone number. But freepbx is stripping off the leading zeros when dialing. Looking at the logs I see this is because a function called sub-flp-3 in extensions_additional.conf wich has the following code:

exten => s,1,ExecIf($[${REGEX("^00[1-9][0-9#\*\+]+$" ${DIAL_NUMBER})} = 1]?Set(TARGET_FLP_3=${DIAL_NUMBER:2}))
exten => s,n,GotoIf($[${LEN(${TARGET_FLP_3})} != 0]?match)

if I comment out this lines then everything is fine but with any change in the freepbx setup it changes back.

What can I do to make this modification permanent?

Check the Outbound Routes and Trunk modules, make sure the entire number is in the number box and you dont have anything in the prefix box. Mouseover will explain.