sendmail appending domain names incorrectly
I'm trying to get my hands on this issue. My log file is filling up with :
550 5.1.2 <MYEMAIL@MYOTHERDOMAIN.COM.www.MYDOMAIN.com>... Host unknown (Name server: MYOTHERDOMAIN.COM.www.MYDOMAIN: host not found)
I think this is wrong, and I've missed some mails, but can't find them in this log file or anywhere else for that matter. I'm supposed to recieve a bunch through php activating sendmail.
Not having fun trying to learn sendmail! :D
Let me know if we need more information to tackle this.
Obviously it's appending my domain name to the outbound destination?
thanks for any help or suggestions