europa.eu thinks otherwise: "To start the procedure, Form A must be filled in, giving all the details of the parties and the nature and amount of the claim. The court will examine the application, and if the form is correctly filled in, the court should issue the European Payment Order within 30 days.
The European Payment Order must then be served on the defendant by the court. S/he can either pay the amount of the claim, or contest it. S/he has 30 days to lodge any statement of opposition to the European Payment Order. If this happens, the case must be transferred to the normal civil law courts to be dealt with under national law."
e-justice.europa.eu/content_european_payment_order-41-en.do
If they could then it would open up shopping for the best jurisdiction.
But without this people can be forced to pay money which they simply do not owe under their law. So we'd have adverts on TV along the lines of 'Son-in-law just won the lottery but won't give you a bean? Move to Poland and we'll sue the bastard for parental support on your behalf'.
Had to do a bit of research on this just in case the outcome was nasty.
But I'd be guessing that the case you investigated was either alimony or child support, both of which would apply under UK law.