The Restoration team website mentions that the PAL video was a DEFT conversion.

As mentioned above, the preferred method of converting film-based content that has been hard telecined with 3:2 pulldown to 30fps is to IVTC back to 24fps then speed up to 25fps.

While a DEFT conversion purports to do this, it does all other kinds of shit as well. So you end up with video that has 4% speedup and blended fields - DVD buyers in PAL-land have been disappointed with the results of these types of conversions (Star Trek TNG and Futurama are two that spring to mind). See also this thread at Doom9.

I've found an AviSynth script function at Doom9 called unDEFTmatcher() that may help, there's also one called RepairDEFT() on another forum but that site appears to be down at the moment.