I am trying to set up emailing from a java web application hosted on a linux server (Cent OS) in apache.
Sendmail is working fine from the command line as root on localhost but when trying to send emails from the java web app (also on the same server from localhost) the following java exception is thrown.
501 5.0.0 HELO requires domain address
EDIT: I have read that some people have found this is due to an incorrect hosts entry currently the hosts file contains
127.0.0.1 Centos-VPS localhost.localdomain localhost
and i'm not sure what the Centos-VPS bit at the start is for but this is a clients hosted server so don't really want to break stuff
EDIT see the RFC is helpful ...
501 Syntax error in parameters or arguments
Now I know what the problem is! (note the sarcasm people.)