"Despite the success of "I'm Real", there was controversy over the use of the single's sample and the structure of the song. The song contains an uncredited sample from Yellow Magic Orchestra's 1978 hit "Firecracker" (an electronic synthpop cover of Martin Denny's 1959 melody of the same name), while the remix on the other hand officially interpolates the Mary Jane Girls' 1983 song "All Night Long" as well as borrowing the melody from Rick James's "Mary Jane." There have been reports that the "Firecracker" sample was originally planned to be used for Mariah Carey's "Loverboy". According to the music publisher of "Firecracker", Carey called to license a sample of the song which had never been sampled months before Lopez called to do the same. Carey rightfully felt that former husband and music executive at Sony Music (Columbia Records), Tommy Mottola, was interfering with her career by arranging for the sample to go to Lopez.[5] Upset by the conduct of Lopez and her ex-husband, Carey featured a reference to the song on her single "Loverboy", her first single released by her then-record company, Virgin Records. The verse can be heard in Da Brat's rap section, where she sings, "Hate on me, much as you want to, you can't do what the **** I do, *****es be, emulating me daily" over the melody of "Firecracker". The word "*****" was used in the song, but when the song aired on the radio, the word "*****" was deleted and the song was cut down to three and a quarter minutes long. Irv Gotti, who produced the remix of "I'm Real" featuring Ja Rule, openly admitted during an interview with XXL magazine that Mottola contacted him with instructions to create a song that sounded exactly like a song he had made with Carey for the Glitter soundtrack[6] entitled "If We" also featuring Ja Rule."
http://en.wikipedia.org/wiki/I%27m_R..._Lopez_song%29
"Throughout 2000, Carey had already been writing and recording material for Glitter.[13] During this period, she developed the concept for the album's lead single, "Loverboy". Originally, Carey had sampled the melody and hook from the 1978 Yellow Magic Orchestra song "Firecracker", using an interpolation of it throughout the chorus and introduction.[13] In early theatrical trailers for Glitter, the original version of "Loverboy" was still featured. As Carey had ended her contract with Columbia Records, Jennifer Lopez was signed by Tommy Mottola, and had begun recording material for her album, J.Lo (2001).[13] According to The Inc.'s Irv Gotti, Mottola, head of Columbia and Carey's ex-husband, knew of Carey's usage of the "Firecracker" sample, and attempted to have Lopez use the same sample before her.[13] At the time, Carey had become increasingly paranoid over outside executives being informed about Glitter, especially following news of Lopez's "theft" of the song.[13] When the music publisher's for "Firecracker" were questioned, they admitted Carey had licensed usage of the sample first, and Lopez had signed for it over one month later, under Mottola's arrangement.[14] Following the scandal, Carey was not able to use the original sample, as Lopez's album was to be released far earlier than Glitter.[14] She subsequently changed the composition of "Loverboy", and incorporated a new sample, "Candy" by Cameo.[14] According to Gotti, Mottola contacted him with instructions to create an additional song that sounded exactly like another Glitter track he produced, titled "If We" featuring rappers Ja Rule and Nate Dogg.[14] The "Firecracker" sample was eventually used by Lopez on her song "I'm Real", from her album J.Lo.[14]
"
http://en.wikipedia.org/wiki/Loverbo..._Carey_song%29
credits to MConnoisseur2;