/**
 * isInteger
 *
 * Gets called onkeydown
 *
 * @param objectsKeyDownEvent	event fired from <input> tag
 */
function isInteger( objectsKeyDownEvent ) {

	var keynum;		// keystroke number code
					// var keychar;
	var isInt;		// boolean
	var isXorY;		// boolean

	if (window.event)
	{
			keynum = objectsKeyDownEvent.keyCode;	// For IE

	} else if (objectsKeyDownEvent.which){

			keynum = objectsKeyDownEvent.which;		// For Netscape, FF, ...
	}

	//keychar = String.fromCharCode(keynum);

	isInt = /^(8|9|13|20|35|36|37|38|39|40|46|48|49|50|51|52|53|54|55|56|57|96|97|98|99|100|101|102|103|104|105|144)+$/.test(keynum);

	isXorY = /^(88|89)+$/.test(keynum);			// 16 is shift key

	if ( objectsKeyDownEvent.shiftKey ) {
		return false;
	} else {
		return (isInt && !isXorY ? true : false);
	}

}