[Freeswitch-users] loopback/XYZ doesn't contain variables from channel

I've got directory with subscribers containing a variable called "country_code". This variable can be used in regular dial plans and works perfectly. However, I've got a conference call dial plan where I use conference_set_auto_outcall. I'mm calling loopback/XYZ to get my other dial plans into play. Everything works, except my subscriber variable "country_code" doesn't get recognised after the loopback/. How can I fix this kind of issue?