Outlook 2007 SP1 stripping some attachments

[roger]

Last week I installed SP1 on two of my computers. Now when I forward emails
as attachments, Outlook removes some, but not all, of the attachments and
replaces them with this:

ATT01056.eml (0 bytes) (154 B)

I disabled AV & Firewall and sent the attachments to myself and got the same
result.

The attachments are a collection of bounce messages. I have been doing this
once a month for several years going back to Outlok 2003 with absolutely no
problems.

Messages being stripped are the short "Returned Mail: see transcript for
details" variety. The longer, more detailed bounce messages come through ok.

Any ideas?

Thanks in advance.
Roger