Los Angeles: Lindsay Lohan`s ex-girlfriend and DJ Samantha Ronson has hit out at comedienne Joan Rivers for calling the actress "dumb".
The DJ was infuriated after reading Rivers` rant against Lohan on microblogging site Twitter, where she wrote, "Lindsay Lohan is so dumb. Her idea of being sworn in is cursing at the judge."
Aceshowbiz.com reported Ronson stepped up to defend Lohan, declaring: "Hey Joan Rivers. You have collagen older than Lindsay, pick on someone your own age, oh wait I guess people that old can`t hear."
Ronson`s support for Lohan touched the actress, who tweeted: "Thank you".
Lohan was sentenced to serve 90 days behind bars earlier this week for violating the terms of her probation on a 2007 DUI arrest. She was photographed in the courtroom sporting a multi-coloured manicure with `f**k u` painted on the nail of her middle finger.