Add countrycode to callerid


I would like to add the country code +46 and remove the leading 0 to the callerid when i do a outgoing call, I tried some different suggestions I foundation on the net, but I dont get it to work.
We are using version 11.6 of Asterisk.
Any hints how to fix this would be greatly appriciated…

core show application set

core show function CALLERID … +Variables

Also, if you have tried something and it has failed, include details of what you tried and the logs showing the failure.