Nicole Richie Hacks Kim Kardashian's Twitter for April Fools' Day

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Looks like the joke was on Kim Kardashian.

Nicole Richie, 28, hacked into Kardashian's Twitter account and posted dirty messages all day Thursday as an April Fools' gag.

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"She got my password from Khloe!" Kim, 29, tells "Nicole twittered it was her and we were emailing! She admitted it. Nicole totally pranked me when I thought no one could fool me on April Fools'!"

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Richie's Tweets under Kardashian’s name included, "Sometimes I think I am a lesbian because HOT DAMN I think Nicole Richie is fffooooiiinnneee!" and "By the way @Joelmadden might be the hottest man alive. I loveeeeee a good daddy."

(Richie also took over her fiance's account as well Thursday, writing to Paula Abdul, "I wanna smell your armpits," and to Disney star Ashley Tisdale, "Hubba hubba.")

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Kardashian snatched back her Twitter Friday morning and admitted, "That was hands down the funniest April Fools'!!!"