The Man of Steel, Vol. 1 #5A

Though he hates Superman for swaying the citizens of Metropolis away from him, Lex still wants to have a Superman on his payroll. To this end, he funds a chinese scientist to scan Superman on a molecular level in order to duplicate him exactly. However the plan is flawed, built around the assumption that Superman is human. Lex is intrigued by the revelation that Superman is an alien, but this causes the duplicat to be disfigured and useless to him.However, the clone still has Superman's memories and feelings and escapes to Metropolis. Superman has to reign the clone in before it does something that might clue Lois Lane into the fact that he's really Clark Kent.