Our mailgateway (Mailsweeper 5) has a spam filter, which adds a special
header "spam detected" at the beginning of a spam mail, so that users can
sort out this mail with an inbox rule.

When my mailbox resides on an Exchange 5.5-server, the header is available
in Outlook, when my mailbox is on an Exchange 2003-server, the header is not
there anymore.

Does anybody now the reason for this?

Exhange send permissions
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