Crystal Palace manager Ian Holloway announced that Bent had chosen Craven Cottage over Selhurst Park but Jol, who bought the 29-year-old when at Tottenham in 2007, denied a deal had been done.
"I don't know what's happening. Darren's probably doing his own thing. We're not sure about it," the Fulham boss said.
"We don't speculate on players and can only give an answer when a deal is finalised. We'll see in the next day or two."
Bent swapped Sunderland for Villa for £24million in 2011, but fell out of favour with manager Paul Lambert last season following the emergence of Christian Benteke.
"We need quality up front and we're trying to get someone in that position in the next week. We need some pace up front," Jol said.
- Ian Holloway