Customizing Google Maps information bubble

How would I customize the Google Maps information bubble when a user clicks on th开发者_开发技巧e red pin? For instance, I want add an input text field and a submit button within the bubble.

Thanks.

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You can put HTML into the infowindow

Here's google's examples

http://code.google.com/apis/maps/documentation/javascript/examples/infowindow-simple-max.html