It used to be the case in Euro Land that you could fly a jet on a PPL with an IR and a full type rating.
I am now told you have to pass either all or part of the ATP ground exams as well?
To fly a turboprop or a jet you need the HPA and passing the 14 JAA ATPL exams is one way to get that.
Another way to get it involves passing the single FAA ATP written exam, which is quite interesting
This issue is being faced by pilots of N-reg PA46s and N-reg TBMs, who, it appears, from 2014, will have to get the HPA to continue flying if their "operator" is EU based. And King Airs, etc. There is some strange stuff going on in that for a PA46 you need an EASA TR whereas for a TBM it is "only" a Class Rating.
The other issue is that few if any TRTOs will let you do a TR unless you have an IR and have passed the ATPL theory.
This stuff is in a state of flux AIUI.
Basically the chickens are coming home to roost on the totally politically motivated EASA FCL "screw N-regs" crap and all the drafting cockups inherent in that, which were sneaked onto the law books by conning key members of the EU Transport Committee by feeding them a pack of lies about a treaty with the FAA being "just around the corner". Nobody ever considered the case where a TR or a CR is not required by the State of Registry, but is required by EASA FCL.