It is too early for that, no legal research has been done both on the Polish or on the German side yet.
I have recently written a university paper about the Oder-Neisse-line and from what I have remembered, the issue of reparations is legally closed. The arguments are as such:
1. Article IV. of the Potsdam Protocol deals with the issue of reparations, there is a passage regarding Poland:
"The U. S. S. R. undertakes to settle the reparation claims of Poland from its own share of reparations."
The SU took huge parts of the German industry, money and natural ressources as reparations. I don't know how much ended up in Poland, but that would be up to the SU. It is worth pointing out that until the border treaty between Germany and Poland in 1991, Poland insisted that the Potsdam Protocol was absolute (because it wanted the Oder-Neisse-line to be final).
2. Poland agreed to wave its' rights to reparations with the GDR. The fact that neither country was a democracy is from a legal point of view completely inconsequential, otherwise it would be impossible to get legal agreements with non-democracy. It is also completely inconsequential if those treaties were signed under outside pressure, because then peace treaties would of course also become in general not binding. So JK's argument is completely ridiculous.
3. Germany and Poland agreed to solve the issue permanently during the negotiations for the border-treaty in 1991. Germany created a foundation that paid out several bns to Polish victims of the war.
Besides, it is not really in Poland's interest to open this can of worms. Because then those Germans who were expelled could demand reparations for their lost property (the Potsdam agreement that legally allowed those expulsions would become non-binding due to Poland's insistence) and there is also the issue of looted art (the Berlinka collection for example) which Berlin has so far not pressed because of respect to Polish sensitives, but would also become open to discussion.
this cant be used as war reparations.if Poland would have to give away former german land in order to recive reparation-as you suggest,then what about polish land in the east we lost?
That would be an issue you would have to discuss with Russia. However regarding Germany, the intent of the Potsdam Agreement was very clear. Poland would receive German land and property and additionally whatever the SU would deem suitable from their part of the reparations. There is no additional claim here. And strictly speaking, the German territory was far more valuable (in terms of ressources and industry) than the part lost in the East.