Mailcheck and pseudo message in a mailbox

[Yarda]

With bash-4.0 the mailcheck behaviour is annoying when there is a pseudo
message in a mailbox, e.g.:

-----
#cat /var/mail/yarda
>From MAILER-DAEMON Wed Sep 30 14:07:09 2009
Date: 30 Sep 2009 14:07:09 +0200
From: Mail System Internal Data <MAILER-DAEMON@onyx.mbox.eu>
Subject: DON'T DELETE THIS MESSAGE -- FOLDER INTERNAL DATA
Message-ID: <1254312429@onyx.mbox.eu>
X-IMAP: 1254311191 0000000002
Status: RO

This text is part of the internal format of your mail folder, and is not
a real message.  It is created automatically by the mail system software.
If deleted, important folder data will be lost, and it will be re-created
with the data reset to initial values.

-----

When the bash starts it reports:
You have mail in /var/mail/yarda

It is very annoying especially in cases when starting bash frequently
(e.g. from Midnight commander), because this message appears frequently.

I think the bash should understand the pseudo message or there should be
a switch for disabling old mail reporting.

Or is there any way how to get rid of this message without removing
metadata from mailbox or disabling mailcheck entirely?