sådan ... så burde den være der :P
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http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="content-type" content="text/html; charset=iso-8859-1"><title>Ingen titel</title>
<script type="text/javascript">
arrd=["01-01-2007","03-03-2007","11-11-2007"];
f="";
window.onload=function(){f=document.forms.formnavn;
recalc(f.date1,2);recalc(f.date2,1);}
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<body leftmargin="0" rightmargin="0" topmargin="0">
<form name="formnavn">
<select multiple="multiple" onchange="recalcfwrd(this,2);" id="date1">
<option value="01-01-2007">01-01-2007</option>
</select><br>
<select multiple="multiple" onchange="recalcfwrd(this,1);" id="date2">
<option value="01-01-2007">01-01-2007</option>
</select>
</form>
</body></html>