Fixing bouncing mobs

[provocating]

Reading back over an old post said that the reason mobs bounce in some zones, but not others is from there spawn point z-axis being off. But I changed that to the same z-axis I was standing on, rezoned back into the zone and that mob still bounces. It would seem to me that the mob would bounce because of another reason, like a problem in the terrain right ? Do the mobs use the *.map file to find where to walk ?