Thx once again. Due to your help my hosts have managed to fix the problem. But they had to disable Nginx to do that, and now the load on my machine is rising!

I was finally able to track down that the Nginx daemon we have sitting in front of Apache was breaking this. I have temporarily disabled Nginx to show you that its working now.

The below thread covers somebody else having the same problem.
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However, with nginx disabled the load on your machine is beginning to climb.

Please let us know if you would like us to leave it as it is now or re-enable Nginx.
Any ideas on a workaround?