eM client claims s/mime signed message signature invalid

I’m in test phase of new email client for our team and got a problem with checking s/mime signed emails.
I have an example of the mail message (in eml format) that email clients Outlook, Postbox, Thunderbird, LiveMail, The Bat says the message signature is valid but emClient - for it the signature is invalid (checksum not the same). Any idea how it is possible? I can provide you with the sample (unfotunately there is not possible to attach other file than image).


Never mind, I found an configuration issue in MTA we use.


thank you for your update on this issue.