Tmail talk - Jun 2008 - TMail cannot determine content type for attachment

Hi, the first mail I wrote on this got suspended and awaits moderator  
approval, I''ll repost here without the offending attachment - so  
pardon if this gets here twice.

My problem is, that TMail returns nil on the content type for the mail  
here: http://pastie.org/210044

Loading development environment (Rails 2.0.2)
 >> mail = TMail::Mail.parse(IO.read("#{RAILS_ROOT}/test/fixtures/ 
inbound_mailer/attachment_type.eml"))
=> #<TMail::Mail port=#<TMail::StringPort:id=0x1051a4e>
bodyport=nil>
 >> mail.attachments.first
=> #<TMail::Attachment:0x207b9ec>
 >> mail.attachments.first.original_filename
=> "Picture 7.png"
 >> mail.attachments.first.content_type
=> nil
 >>

This is not a general problem I see, any ideas what''s wrong with the  
email (or tmail)? Thanks.

Morten