Problem using this Exim ACL

[bsasninja]

There is a ACL for blocking hostnames with "localhost" in it posted in several sites, but the problem is that if the machine of the person sending the email is called "localhost" the mail will not arrive.

For example, if you use WinXP try setting your machine name to localhost then send an email with this rule in your server... it will be filtered.

deny message = You are hardly local, fool
log_message = HELO/EHLO localhost
condition = ${if match {$sender_helo_name}{localhost}{yes}{no}

Is there a way to filter the sender "server" host if its called localhost instead of the name of the sender´s machine?

Thanks