function wopen(url, target, width, height)
{ 
window.open(url, target,"toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=yes,width="+width+",height="+height); 
}

function txtCounter( field, countfield, maxlimit ) {
	if ( field.value.length > maxlimit ) {
		field.value = field.value.substring( 0, maxlimit );
		alert( 'Text může mít pouze 1000 znaků.' );
		return false;
  }
  else {
  countfield.value = maxlimit - field.value.length; 
	}
}