How to set the default (submit) button for a page loaded in an iPhone UIWebView (stringByEvaluatingJavaScriptFromString?)

Question

Hi, I'm using a UIWebView to load an HTML form in my iPhone app.

The form has three submit buttons (and selecting "Go" on the iPhone keypad selects the first submit button).

I'm assuming that I can set a different "default" submit button with Javascript injection into the downloaded form, but I don't know Javascript well.

Does anyone know how to change the default submit button ?