[Exim] how do you override default helo

Hi,

I'm new to the list, and to Exim. I've use qmail for years and just
made the switch...
I've had a couple of emails bounce on me with following error...
SMTP error from remote mailer after RCPT TO:<somerecipient@???>:
    host mail.isp.com [66.xx.xxx.xxx]: 504 <DEA01FW-Clean>:
    Helo command rejected: need fully-qualified hostname

My mail server host name is infact DEA01FW (not-Clean)
In qmail I could change the host name sent to a HELO query by editing
a helo config file... How do I do the same in Exim 4.22? I'd like it
to respond with mail.mydomain.name.

I've tried going through the Exim Spec, can't find it easily.

Any help would be appreciated.
Thanks
Dean

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Dean Staff Kanata On. Canada
A+, MCP, MCSA, MCSE, CIW Security Analyst
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