eNom, one of our favourite registrants, resells SSL certificates - as many other registrants do. One of the providers is SBS - Secure Business Services. SBS's offerings claim 99% browser compatibility. Our research shows otherwise.
After installation of these certificates and the necessary gd_bundle we saw SSL exceptions on the following browsers: Firefox on Linux, Safari on Mac, Safari on iPhone, Blackberry Browser. So after five minutes of testing it appears that 99% browser compatibility is a false claim.
The other certificates offered by eNom and SBS, while more expensive, are still not recognised with these very common and popular browsers (maybe not the most popular, but > 1% for sure).
If using eNom to purchase SSL certificates simply bypass the SBS certificates and choose another option. The GeoTrust certificates appear to be more compatible. If you need a refund on the SBS Instant certificate use the eNom ticket system - calls to sales or support will simply direct you to the ticket system.
In an odd twist of fate, while helping our client re-issue using GeoTrust the eNom portal was having odd problems on checkout - would not recognise our option of 'Outside Hosting' (error said we needed to get hosting) and the initial view of the CSR submission page told us the CSR was invalid (the CSR we had not yet generated or submitted).
What is going on over there eNom? I've been a client for close to ten years and your service level seems to be dropping off. Please advise.