I’d like to follow-up on this…
I have the same behaviour – WHOIS-loopup from the plugin works well on localhost environment, but results in a blank page on the productive site.
No matter how long I wait, the WHOIS results do not show up, altough giving the “WHOIS lookup successfully completed”-message.
This happens for ALL lookups I tried so far, not for specific IP-addresses.
Any ideas?