Weaver, 26, is not only a fullback but he can also carry the ball -- he averaged nearly 4.5 yards per carry over his three NFL seasons.
The Eagles addressed a huge need by signing Weaver. The Birds spent last season without a true fullback -- they often were unable to gain first downs in short yardage situations.
The Eagles needed a guy who can clear the way in short-yardage situations. Weaver is a blocking back who also can catch the ball out of the backfield.
Weaver had 352 total yards (222 receiving) from scrimmage with two TD receptions for the Seattle Seahawks last season.
The deal is worth $1.75 million but could reach $2.5 million with incentives, sources told ESPN.com.
Weaver was an Division II All-American tight end at Carson-Newman College. He originally signed as a rookie free agent with Seattle in 2005.