[exim] mandate ehlo before mail while sending out email

Hi all,


1 of my client sent an email to hallmarklabels.com but he didn't succeed.

Here's what the log said:
2006-01-05 17:49:32 1EuRhL-0005l7-SW ** <sender@???>R=dnslookup
T=remote_smtp: SMTP error from remote mailer after RCPT TO:<
recipient@???>: host uk2mxarray4.uk2.net [83.170.64.217]:
550-EHLO/HEL0 argument (localhost) must be a syntactically-valid\n550
fully-qualified domain name or address literal

Therefore, i have 2 questions
1) does EXIM by default use EHLO/HELO before MAIL command when sending out
mails ?
2) if not, how can i mandate it to issue EHLO/HELO before MAIL?

i'm runing exim 4.5 on debian sarge.


Please help.
Thanks