google ignores my ip.. pr checker tools on my site don't work anymore, what to do?

I have a webmaster site (see my sig), with a pr checker tool here

Everything works fine, exept the pr checker. The tool works on other sites (like www.myprchecker.com), so it's not the code, but my ip. Why? and what can i do about it?

i'm getting a bit desperate i can't find the answer anywhere