I've solved the issue. pgagent.pga_job.jobhostagent must be blank. Thanks to this link http://forums.enterprisedb.com/posts/list/1419.page
Anyway, the docs say ... "optionally the hostname
of a specific machine running pgAgent, if this job should only run on
that specific server. If left empty, any server may run the job. This
is not normally an issue for SQL-only jobs, however any jobs with
batch/shell steps may need to be targetted to a specific server." ..., so why didn't it work when I specified the host of 127.0.0.1 or localhost?
Thanks
