Differences
I'd like to point out that there is not a single JAA member state, that has not filed some or other difference in regulations or procedures to the JAR requirements. The French age 60 rule, the British licence format, the Dutch licence signing by local TRE's only, the Swiss issuing Swiss ATPL's, the Italian age 60 rule, and so it goes on...
As for Flying in France over age 60; some companies do, and some companies don't. Whether it is legal or not is irrelevant when it comes down to a matter of whether your company cares or not. Farnair Switzerland don't give a hoot and routinely put an over 60 captain on the BSL-CGN route flying over France.