function toggle_checked(prefix){
	var strBokser = '';
	var blnSomechecked = false;
	var blnSomenotchecked = false;
	var arrBody = document.getElementsByTagName("body");
	var sfEls = arrBody[0].getElementsByTagName("INPUT");
	for (var i=0; i<sfEls.length; i++) {
		var objElement = sfEls[i];
		if(objElement.type == 'checkbox' && objElement.id.substr(0,prefix.length) == prefix){
			if(strBokser != '') 
				strBokser += "," + objElement.id;
			else
				strBokser += objElement.id;
			
			if(objElement.checked) 
				blnSomechecked = true;
			else
				blnSomenotchecked = true;
		}
	}
	
	var arrBokser = strBokser.split(",");
	for (var i=0; i<arrBokser.length; i++) {
		var objElement = document.getElementById(arrBokser[i]);
		if(blnSomenotchecked){
			objElement.checked = true;
		}
		else {
			objElement.checked = false;
		}
	}		
	
}