Form Submissions Gone Mad

[filburt1]

<form action="..." method="..." onsubmit="document.getElementById('submitbutton').disabled = true">
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<input id="submitbutton" type="submit" />
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</form>

A client-side method is not desirable. Use a server-side method such as reading the last date/time the user submitted the form and reject submissions made less than, say, 5 minutes ago.