Jason Alexander (born Jason Scott Greenspan on September 23, 1959) is a television, cinema and musical theatre actor, best known for his role as George Costanza on the hit television series Seinfeld.

He’s 48!

Alexander was born in Newark, New Jersey to Josh and Ruth Greenspan. He has a half-sister, Karen Van Horn, and a half-brother, Michael Greenspan.

Alexander is Jewish. Alexander is a 1977 graduate of Livingston High School in Livingston, New Jersey. He had also attended Boston University, but abandoned his studies the summer before his senior year after getting work in New York City. He was later given an honorary degree. In September 2006 on Access Hollywood, he identified Robert Lampf as his favorite teacher and the teacher that most influenced and encouraged him to pursue his acting career.

Alexander is best remembered as a cast member of the award-winning television sitcom Seinfeld, in which he played the neurotic ne’er-do-well George Costanza, Jerry Seinfeld’s best friend.

Concurrently with his Seinfeld duties, Alexander provided the voice of the lead character in the cult animated series Duckman, which lasted from 1994-1997. Alexander also voiced Catbert, the evil director of human resources, in the short-lived Dilbert animated series based on the popular comic strip. He appeared in the second season of Curb Your Enthusiasm playing himself.

Jason Alexander also had a part in Dinosaurs on ABC as a character named Al (Sexual) Harass. His character used to talk about sexual harassment in the work place.

Despite a relatively successful career in film and on stage, Alexander never managed to re-capture his Seinfeld reputation on the small screen. 2001 marked a brief but highly-touted return to prime-time with the sitcom Bob Patterson, canceled after 5 episodes.

Alexander appears on the Family Guy: Live in Vegas CD singing a verse in the song “All Cartoons are Fuckin’ Dicks”.

Alexander is credited with coining the term “asshat” in a well known blooper from the show “Seinfeld”.

He was featured in the Friends episode “The One Where Rosita Dies” as a suicidal supply manager named Earl. Phoebe rings him trying to sell him toner and she learns about his problem and tries to convince him not to commit suicide. This is referred to in an episode of Malcolm in the Middle where Alexander appears as a neurotic and critical loner called Leonard. He describes himself as free and mentions that he makes money with a job “selling toner over the phone”. Also in the episode, he is repeatedly harassed by a man named George - his character’s name on Seinfeld.

Alexander appeared on Star Trek: Voyager on the episode “Think Tank” playing a genius alien named Kurros who was trying to get Seven of Nine on his ship.

He appeared in the first episode of the short-lived 2002 revival of The Twilight Zone, playing Death.

He featured in the 2005 Monk episode “Mr. Monk and the Other Detective” as Monk’s eponymous rival, Marty Eels.

On the June 26, 2006 episode of the Jimmy Kimmel Live talk show, Alexander demonstrated several self-defense techniques. He was also the Host of the 230th July 4, 2006 of the PBS July 4 “A Capitol Fourth” Celebrations in Washington, D.C. in which he sang, danced, and played tuned drums.

Alexander has appeared twice on Bravo’s Celebrity Poker Showdown and won the final table in the 8th season. Alexander played for United Way of the greater New Orleans area and won $500,000 for the charity.

On August 6, 2006, Alexander signed on to feature as a regular cast member in the second season of Everybody Hates Chris.

Alexander was the host of the Comedy Central roast of actor William Shatner on August 13, 2006, which first aired on August 20, 2006.

In 2007, Alexander was a guest star in the third episode of the improv comedy show Thank God You’re Here.

Other September 23rd Birthdays:

Mickey Rooney-Actor/Comedian -87
Julio Iglesias-Singer -64
Mary Kay Place-Actress/Writer for M*A*S*H -60
Bruce Springsteen-Singer 58
Kip Pardue-Actor -31

and Remembering…
Ray Charles -77