UpdateComboOptions(f.MyFld, 'a');


function UpdateComboOptions(fld, mtype) {
	if (fld == undefined) {
		return false;
	}
	// reset values to none
	fld.options.length = 0;
	// add values back
	if (mtype == 'a') {
		fld.options[fld.options.length] = new Option('First 1', '1');
		fld.options[fld.options.length] = new Option('Second 2', '2');
		fld.options[fld.options.length] = new Option('Third', '3');
		fld.selectedIndex = 0; 
		fld.size = 3;
	}
	if (mtype == 'b') {
		fld.options[fld.options.length] = new Option('Alt First 5', '5');
		fld.selectedIndex = 0; 
		fld.size = 1;
	}
} 