Globalsign sends Mails through, technically via google Mailservers

We got a SSL certificate renewed. This is what we got:

Jun 25 12:10:18 smtp postfix/smtpd[7927]: ... RCPT from[]: 
      450 4.2.0 <>: ... from=<> ... proto=ESMTP helo=<>, a nameserver, is sending SSL renewal mails? Whatelse is running on those machines? The perlscript that creates/signes the certificates, webserver, etc. Is globalsigns private key to sign the certificates also on this machine?

Oh my…

The MX for globalsign is google-mail:

# dig -t mx

;            IN  MX

;; ANSWER SECTION:     900 IN  MX  20     900 IN  MX  20     900 IN  MX  10     900 IN  MX  30     900 IN  MX  30     900 IN  MX  30     900 IN  MX  30

Thats why i only trust myself and create only self-signed-certificates for my services. I do not throw money at those companies that just start a perlscript to generate a ssl-cert i can create the same way…