function getObj(nm) {
	if (document.getElementById) {
		return document.getElementById(nm);
	} else if (document.all) {
		return document.all[nm];
	} else {
		return eval("document." + nm);
	}
}

function buttonOn(buttonID, image) {
	getObj("buttonImage" + buttonID).src = "graphics/nav_" + image + "_on.jpg";
}

function buttonOut(buttonID, image) {
	getObj("buttonImage" + buttonID).src = "graphics/nav_" + image + "_off.jpg";
}

function lighteningalterBG(obj, backgroundcolour, textcolour) {
		obj.style.background=backgroundcolour;
		obj.style.color=textcolour;
}

function removevalue() {
	if (getObj("emailaddress").value == "Enter Email Address" ) {
		getObj("emailaddress").value = ""	
	}
}

function validateFileExtension(fld) {
	if (fld.value != "" ) {
		if(!/(\.doc|\.pdf|\.xls|\.txt)$/i.test(fld.value)) {
			alert("You have tried uploading an invalid file type, please use .doc or .pdf");
			//fld.form.reset();
			fld.focus();
			return false;
		}
		return true;
	}
}