U.S. comedienne Sarah Silverman regrets poking fun at Paris Hilton on the eve of her June (07) jail stint after watching footage of the Mtv Movie Awards.Silverman, who hosted the awards show, joked about Hilton's prison term, while the hotel heiress sat awkwardly in the audience.Cameras captured a hurt Hilton as she squirmed in her seat - just hours before she began her prison sentence for a probation violation at Century Regional Detention Center - and Silverman admits she has felt terrible ever since.She says, "I thought, 'She's got to know there's going to be a joke about her,' so I went for it. But then I looked down and saw a man in her face with a camera."I was there to be funny and I was, but that doesn't mean I can't feel bad about it."A forgiving Hilton admits she knows Silverman was just trying to land a few laughs: "She's a funny comedienne and hopefully she won't be as mean the next time she sees me."