Unhandled Error!

			if (!$this->is_column_cache_disabled())
			{
				if (!array_key_exists($this->className, self::$cached_column_definitions))
					self::$cached_column_definitions[$this->className] = array();
 
				if (!array_key_exists($dbName, self::$cached_column_definitions[$this->className]))
					return self::$cached_column_definitions[$this->className][$dbName] = new Db_ColumnDefinition($this, $dbName, $displayName);
 
				return self::$cached_column_definitions[$this->className][$dbName]->setContext($this);
			} else
				return $this->column_definitions[$dbName] = new Db_ColumnDefinition($this, $dbName, $displayName);
		}