iOS iPhone Keyboard pop up on focus of input box of html page

Hi,

I am new to iphone developement and this is my first post on this forum.

I have created a webview which loads one local html page.
This html page has one text box and some radio buttons.
But when I select the textbox there is no keyboard pop up and I can't enter text into text box.
So what to do get keyboard pop up enable on selection of text box.
Please note that I am not using UITextField. It is textbox created by html page.
Please help me this.

Thanks,
Shashikant Deokar