function setVolumeControl(formname,parametername, value) {
	//alert (formname+", "+parametername+", "+value);
	var forminputelement;
	/*if (eval("document."+formname) && eval("document."+formname+"."+parametername)) {
		forminputelement=eval("document."+formname+"."+parametername);
	}
	else*/ forminputelement=document.getElementsByName(parametername)[0];
	for (var i=0;i<eval("max_"+parametername);i++) {
		var td=document.getElementById("control_"+parametername+"_cell"+(i+1));
		//alert(td.style.backgroundColor);
		if (i<=value) td.style.backgroundColor=VOLUMEONCOLOR;
		else td.style.backgroundColor=VOLUMEOFFCOLOR;
	}
	//if (!forminputelement) alert ("form input element not found");
	//else alert (forminputelement.value);
	forminputelement.value=value;
}

function incrementVolumeControl(formname,parametername,increment) {
	var forminputelement=document.getElementsByName(parametername)[0];
	var newvalue=forminputelement.value-0+increment;
	if (newvalue>=0 && newvalue<eval("max_"+parametername)) setVolumeControl(formname,parametername,newvalue);
}