An ATPL is only a recognition of higher qualifications and hours, including the right to fly PIC of an airline operation aircraft(s). But that is where it stops. Every country's Civil Aviation organisation has its own requirements, despite your FAA, JAR etc etc. It must meet the ICAO standards as a minimum and the relevant country organisation has the final say. I had to sit the local licence equivalent in every country I fly professionaly its registered aircraft.
