pidfilepath can not have spaces.
If the pidfile has spaces (pidfilepath = /var/run/mongodb/mongodb.pid) then you can not stop the service.
does not work with 2.6.3.
$sudo /etc/init.d/mongod stop
Stopping mongod:                                           [FAILED]
Merge pull request #128 from mkrakowitzer/pidfilepath_fix

pidfilepath can not have spaces.