"It's not quite worked out for him at Southampton," Vale manager Micky Adams told BBC Radio Stoke. "We know very little of him, but the boy knows that.
"It gives me another player for me to look at before the end of the season."
Adams added: "Southampton have kindly accommodated the loan move in terms of the financial side of things, so we're thankful to them for that."
Molyneux will not be involved in the local derby against Crewe on Saturday as Adams believes he is short of match fitness.
"I am just hoping to get some games under my belt, bring something to the team, help them push on, and hopefully make the play-offs," Molyneux told the club website.
Source: BBC Sport
Source: BBC Sport