It's hard to believe, but the always stunning Diane Lane has reached that age where she can play a mother to a an actor or actress in their mid-20s.  Proving that point, Warner Bros. announced this evening that the Oscar nominated actress will join the cast of Zack Snyder's new untitled "Superman" film as Martha Kent, Clark Kent's adoptive mother.

In a statement issued by the studio, Snyder said, “This was a very important piece of casting for me because Martha Kent is the woman whose values helped shape the man we know as Superman. We are thrilled to have Diane in the role because she can convey the wisdom and the wonder of a woman whose son has powers beyond her imagination.”

The 46-year-old actress is now the only confirmed cast member besides Henry Cavill who will play Kent, aka Kal-El aka Superman.  Reports have surfaced that Kevin Costner is on board to possibly play Martha's husband Jonathan, but only Lane and Cavill were confirmed in the studio's press release.

Lane is best known for her roles in "Unfaithful," "Under the Tuscan Sun," "The Cotton Club" and the landmark TV mini-series "Lonesome Dove."  She recently starred in "Secretariat" and will next be seen in HBO's "Cinema Verite" alongside James Gandolfini and Tim Robbins.

The new "Superman" will be produced by Charles Roven, Emma Thomas, Christopher Nolan and Deborah Snyder.  The screenplay is by David S. Goyer based on a story by Goyer and Nolan.  Production is expected to begin this summer for a December 2012 release.