[Exim] SMTP Auth configuration

Ok, I am a little slow at times, so forgive me if this seems simple.

I have setup exim to handle SMTP AUTH and read user info from a MySQL
database. I am configured for both methods (LOGIN and PLAIN). The Login
method seems to work correctly (so program like Outlook Express work fine),
but PLAIN seems to not be working. I have setup plain as follows:

plain:
  driver=plaintext
  public_name=PLAIN
  server_condition = "${if eq{$2} \
        {${lookup mysql{SELECT pwd FROM mail \
   WHERE uname='${local_part:$1}'}}}{1}{0}}"
  server_prompts= "Login::"
  server_set_id=$1

but when Mozilla connects (only windows client I have that wants to do PLAIN
vs. LOGIN) it always rejects. It looks like Exim is receiving the correct
information. I captured the string that was going once and after decoding it
from mime format, it boiled down to (visible characters only) be in the
format <uname><password>. Since the plain method is designed to be
<uname>[NULL]<password> I am assuming that the correct information was sent,
but Exim is rejecting the authentication.

Any help on this is greatly appreciated.

Thanks!
Dan