PAL/NTSSC issues will in fact give a "region code" error message on most brands of players even though it's really not a region issue.
the player gets confused and knows that the disc won't play. most players aren't programmed with ways to detect the error with enough specificity to tell you that you've got the wrong format. it knows that the player has a specific region and that the disc you've put it won't play. even though the disc is region free (if it's a burned disc) you'll still get that region code error if it's the wrong format.
the best solution is to buy a multiformat player (easier to find overseas than in the US from what I can tell...but not impossible)
another solution would be to convert formats using a program like DVDSanta, but you may not be satisfied with the results. few software programs do a satisfactory job with this type of conversion