Emails with Digital Signature not autoforwarded in usual format

[Shiv Kotagal]

Hi,
I have a autoforwarding rule on a Account which is not
working correctly with Emails signed with Digital
Signatures. The '------original message-------' header
which usually appears in a forwarded email is not present
in the autoforwarded emails with Digital signatures. Can
anybody please tell me the cause of this and how it can be
prevented. Is this a bug in Outlook. How do I
programmatically detect a digital signature on an email ?

thanks a million !

Shiv