Keyboard keeps disappearing when writting upon some websites

Hiya, I'm using an iPod Touch 4G I recently bought and while browsing this particular website (neopets.com) and posting on its forums, my keyboard retracts every 20 seconds or so. I can easilly bring it back by tapping the text area again, but it will retract soon again, so it gets annoying. I notice it happens when Safari is showing the loading icon at the top, as if it was kinda refreshing, but it's not like the page reloads, so I'm confused..

Can anyone enlighten this newbie please? Thank you.