Entering a naturally generated dimensional fracture either gives the message "This fracture does not lead anywhere..." or does nothing

Are you using special server software (especially bukkit-based ones) or anything like that? There used to be problems with those kind of servers in the past, but I thought they were all fixed. Also, check your game logs when you try to enter a fracture - the mod may output some debugging information if it can't find a destination for the fracture.