I just checked and you're right. Their website is very misleading on the subject: "The StartCom Certification Authority, provides the StartSSL™ Free certificates instantly, without limitations". Correct me if I'm wrong, but "Class 1 certificates are limited to client and server certificates, whereas the later is restricted in its usage for non-commercial purpose only." is the very definition of a limitation.
Thankfully it doesn't affect me currently -- I'm using class 2 certificates -- but I'll be doing more research come renewal time.
Thankfully it doesn't affect me currently -- I'm using class 2 certificates -- but I'll be doing more research come renewal time.