Very Odd- Taobao Question - Solved, Thanks!

I discovered this just a few hours ago, and checked through the comm's history. No, I don't believe this has been asked before.

Just a few hours ago, I went to TaoBao and noticed something weird pop-up. It had a picture of an American flag, and some mention of overseas buyers. Out of curiosity, I went to register, and noticed it now lets you put in other countries and addresses outside of China. They even accept VISA cards now?

I tried doing a google search, but couldn't find anything about it. Does this mean they are beginning to cater to international buyers, or am I just stupid and am missing something? Before, it wouldn't let you register with an address outside of China, right?

I tried adding my shipping address, and everything went in fine, until I tried to save it. This text popped up "Operation Failed. P must be between 5-10 digits". I am assuming that ment my postal code...But my postal code IS five digits....What?

I'm VERY confused about what is going on. I'm probably just stupid, and this could be easily answered. And light on the subject would greatly help.

Edit: Thank you to everyone who commented. You all helped end my confusion.