What is this song?? "These eyes...are cryin'..."?

There is this song I've been tring to remember the artist of. It is from the seventies, it is kinda' bluesy, and it goes a little somethin' like this... "These eyes... are cryin'! These eyes aaare cryin'! These eyes have seen alot of love but they never seen the kinda' love like I had with you.... Ahhh! These eyes... are cryin'..." Evan, the character in Superbad was singing it at that party where he was mistaken for the guys brother and they're tryin' to get alcohol.