Are you talking about an MSIE modal window? You do know those don't work in any other browser.
If you are talking about a popon <div>, then yes, it should work.
Maybe you could show the code you use to create the modal window?
And no, you can't put an image inside a <input type="button">.
You could put it inside
<button type="button" ....>...text or image or both...</button>
You need to show more of your code.
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A pessimist sees the glass as half empty.
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