Each deal is worth $2.5 million, plus $300,000 in bonuses.
The 35-year-old Langenbrunner is coming off a disappointing season, totaling nine goals and 23 assists in 70 games with Dallas and New Jersey. In 2009-10, Langenbrunner had 61 points with the Devils.
The 36-year-old Arnott is a 17-year veteran and had 17 goals and 14 assists in 73 games last season for New Jersey and Washington. His best season was with Dallas in 2005-06 when he had 76 points.
Arnott was captain of the Nashville Predators for three seasons from 2007-10. He ranks sixth among active players in career games and seventh in points, and has 12 seasons with 20 or more goals.