<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by ec336:
As far as I know, they already do some codesharing with LOT Polish Airlines into Eastern Europe (through WAW).</font>
With all due respect, that's incorrect. Perhaps, you confuse codesharing with ability to earn AA miles on LOT flights (including those to Eastern Europe). The only AA codeshares with LOT are those over-the-water (WAW to ORD, JFK and EWR).
The only current AA codeshares to Eastern European destinations are those with Finnair to RIX (Riga) and TLL (Tallinn).