peoblem when creating a community account

hello,everyone,

I am a user of postgres and wanna to create a postgres community account.

But on the sign up page, i got the message below:

"Captcha field is required."
What confusing me is that the captcha picture did not show up and either input box.

I have tried refresh the page  , change  browser and  update flash and so on. But did not works.

So,anyone can help me out？
thanks a lot~