"And in looking into it some more... My host has mod_cloudflare set up on all its shared servers and most of its dedicated ones.."
All of our hosting partners should have mod_cloudflare installed on their servers already. The only thing I would have them check, if you see an issue, is that they have mod_cloudflare set with CloudFlare's IPs (just in the event they are using an older version). We have updated some new ip ranges on that page recently.