Various Sites are rumoring this through Eddie Murphys Interveiw:
He came to me with an idea for another Cop (Beverly Hills Cop), and we’ve been talking about that.
However Tarantino Recently commented: "ba ding ding ding ding di di ding ding bah bahbeday"
Ha, only joking about the last bit, but has got to just be talk…
Robert Rodriguez’s Conan 3 & Quentin Tarantino’s Beverly Hill’s Cop
What Is Happening?