I noticed being set up with a StartSSL intermediate cert that expires in 2017, which is signed with SHA1. I guess that's going to cause problems?
I just replaced the intermediate cert and the warnings went away.
You can probably download their latest intermediate certificate or bundle (https://www.startssl.com/certs/) to resolve the error.
Notice how their current intermediate cert has a SHA256 hash, yet they don't offer an "old" intermediate cert which would supposedly be required for older certificates.