I'm not sure how this is possible, but this is my experience with BTCChina.

I've got two webservers located in different datacentres here in Australia, one successfully connected to BTCChina using their API via PHP, the other couldn't - exact same code. This suggests that there might be some sort of routing/firewall issue somewhere. My PC at home also couldn't connect. I had begun work on creating a pass-through on the server that worked, simply adding its IP in my hosts file for api.btcchina.com - this was gaining some traction when I read here that people had successfully connected via API after doing a trade. I proceeded to deposit and sell 0.01BTC for market value. Several moments later (roughly 3 minutes) I tried the Haas bot again (after removing the hosts record), the test settings reported that it 401'd, but BTCChina was then available for selection in the "Exchange Website" drop down and I could get my balance using "Show Wallet".

So, for those that aren't having success connecting, looks like its confirmed that all it might take is a simple sell and you'll be in the clear.