The roster move, announced Saturday, comes a day after the release of point guard Gal Mekel.
The club says Smith will be in New Orleans and available for Saturday night's game against Portland.
Smith, a former Louisville standout, was acquired in a draft-night trade after being selected in the second round, 47th overall, by Philadelphia. He has appeared in six games with Fort Wayne, averaging 16.5 points, 6.2 assists and 1.8 steals.
Earlier this season, Smith appeared in three games for New Orleans. In limited minutes, he had one rebound and no points or assists.