SMIME signature failures

I got encryption working with my SMIME implementation, but I am still  
having problems with signed email.  I have attached an email which is  
failing to be verified on my Mac Email program.  Could somebody take  
a look, try to verify it and let me know what the problem is?
thanks,
Robert

SqueakSignedEmail.text
Description: Text document

smime.p7s
Description: S/MIME cryptographic signature