Riether has been an ever-present for Fulham in the Premier League this term since joining on loan from Cologne last summer.
His performances for the Cottagers have already prompted former first-choice right-back Stephen Kelly's departure from the club this month for Reading.
Jol has expressed his delight with Riether and has hinted that the twice-capped Germany international could earn a permanent deal at Fulham.
"Sascha Riether has done a great job for us. He's enthusiastic, mobile and aggressive," said Jol.
"I only wanted him on loan because you never know how they'll do.
"If he carries on like this we will make our mind up and try to extend it or buy him."