We are 3 different companies and would exchange S/MIME encrypted Emails. We work with 3 different mail systems: IBM LotusNotes, MS Exchange and MS Outlook11.
LotusNotes and Exchange works IANA conform with following content type:
Content-type: application/pkcs7-mime; smime-type=enveloped-data; name="smime.p7m"Content-Transfer-Encoding: base64
but Outlook11 is using following content type with additional x-:
Content-type: application/x-pkcs7-mime; smime-type=enveloped-data; name="smime.p7m"Content-Transfer-Encoding: base64
Lotus Notes cannot decrypt such messages and includes an attachment with the name smime.p7m. But the messages with the IANA conform content type from Exchange will be decrypted without any problems. Exchange has no problem with both variants.
My Questions:
Which version is Outlook11 which writes the line "X-Mailer: Microsoft Office Outlook 11" in each Email?
How this Outlook11 client can be influenced to use the IANA conform Content-Type: application/pkcs7-mime.
Outlook10 SP2 should work correctly - which version of Outlook is this?
