I just tried cid lookup with http and it worked perfekt when all on the http server end was fine.
I did some testing of what would happen in a couple of scenarios and the result was so bad i can not use the function in my environment.
Test 1 – http server slow response. Result: Call does not get through until http server responds.
Test 2 – http server gives error response. Result: Call never gets through.
I would sugest that you improve CID Lookup with a custom time out.
I would alsa sugest that you handle bad responses.