(FAQ) As already written you have to copy in yout z-program source the code of the active enhancements as SAP will always comment those (check online help or relative notes like Note 1030740 - Copy of program with enhancement statement is incorrect)
When you copy a program that contains enhancement statements, they are deactivated in the target program.
But just copy the code not the enhancement structures, your are now in a customer program, so not needful. Of course better keep the commented enhancement in the source to reduce the task of the poor guys who will perform the next upgrade project.
Regards,
Raymond
PS: Aniket Zanzan was faster