[Exim] Return Mail Problem

When I send a message from an outside SMTP server on one of
my domains with a bogus local-part exim accepts the mail, and
attempts to send the Reply-To address an email stating the
problem etc... But when exim tries to send it for some reason
the MAIL FROM: gets screwed up like so:

SMTP>> MAIL FROM:<> SIZE=4404

Any advice on how to fix this up is apprciated, or if someone
could tell me how to make it so exim will just not accept mail
for non-recognized local-part would be good too, until than I will
be looking through the manual for possible solutions. Thanks.
BEGIN:VCARD
VERSION:2.1
N:Dunne;Gavin;B;Mr
FN:Gavin B Dunne
ORG:Web Works Inc.
TITLE:Developer
TEL;WORK;VOICE:709-579-4687
TEL;WORK;FAX:709-576-6777
ADR;WORK:;;140 Water Street.;St. John's;NF;;Canada
LABEL;WORK;ENCODING=QUOTED-PRINTABLE:140 Water Street.=0D=0ASt. John's, NF=0D=0ACanada
ADR;HOME:;;;St John's;NF;;Canada
LABEL;HOME;ENCODING=QUOTED-PRINTABLE:St John's, NF=0D=0ACanada
EMAIL;PREF;INTERNET:gdunne@???
REV:20010226T173841Z
END:VCARD