Vivica A. Fox is being backed by her gal pal Star Jones over her decision to marry Atlanta club promoter Omar 'Slim' White, who is 19 years younger than The Cougar reality star, RadarOnline.com has exclusively learned.

Jones -- who went through a tough time when her own 4-year marriage to Al Reynolds ended in divorce in 2008 -- is supporting the engagement, although some of Fox's friends are privately skeptical.

Fox, 46, was deliriously happy after White, 27, popped the question during a vacation in South Beach, Miami, over the holidays after he bought her a $60K, eight-carat diamond ring.