return null;
return loadExtraDriver( className, false );
	private  Class loadExtraDriver(String className)	{		if( extraDriverLoader == null)			extraDriverLoader = new DriverClassLoader();				try		{			return extraDriverLoader.loadClass(className);		}		catch ( ClassNotFoundException e )		{			//re-scan the driver directory. This re-scan is added for users would potentially 			//set their own jdbc drivers, which would be copied to driver directory as well			if( ! extraDriverLoader.refreshURLs() )			{				// no new driver found; give up				return null;			}						// New driver found; try loading again			try 			{				return extraDriverLoader.loadClass(className);			} 			catch (ClassNotFoundException e1) 			{				return null;			}		}	}