//
// Used by validation functions to determine whether the field is empty
//

function checkNotNull(myInput, myMessage) {
	var x=document.getElementById(myInput);	
	if (!x.value) { 
			if (myMessage) { // check for a custom message
				alert(myMessage);
			}
			else {  // default message
				alert("Please enter something in the the "+x.name+" field.");
			}
		x.focus(); 
		return false;
	}
	
}