hadoop (jobtracker) wants fully-qualified hostnames (ie trailing "." suffix)
 ref: http://www.dns-sd.org/TrailingDotsInDomainNames.html

I'm not entirely sure this is required for all installations.
Test by grepping for "Choosing data-local task" in hadoop-xxx-jobtracker.log
 to see if jobtracker hostnames are matching split location hostnames.
upgrade to hadoop-2.2.0