function disableElement(referer, operator, to_check, to_disable, to_enable){
	var to_check = document.getElementsByName(to_check)[0].value;
	var to_disable = document.getElementsByName(to_disable)[0];
	var to_enable = document.getElementsByName(to_enable)[0];
	if((operator == "<" && to_check < 0) ||
	(operator == ">" && to_check > 0) ||
	(operator == ">=" && to_check >= 0) ||
	(operator == "<=" && to_check <= 0) ||
	(operator == "==" && to_check == 0) ||
	(operator == "!=" && to_check != 0)){
		to_disable.disabled = false;
		to_disable.className = "textbox";
		if(to_enable != false){
			to_enable.className = "disable invisible textbox";
		}
	}else{
		to_disable.disabled = true;
		to_disable.className = "disabled invisible textbox";
		if(to_enable != false){
			to_enable.className = "textbox";
		}
	}
}