It depends, it is normal for adaptive uv tiles and some settings in Zmapper.
I recommend using Group UV tiles and getting a Zmapper preset for your specific computer,( software, etc).
Also I recommend that when the Normal map is done reverse the V cordinate
and go to the texture section increase the fix seam value to 25 and hit the fix seam button, then return the V corordinate back to it’s reversed state, then export it as a BMP for use with Mental Ray, or Renderman.
Oh yes and if your using Maya make sure to turn off the texture filtering method completely or else you will get seams.
Great advice, thank you! 