Array of covergroup not supported

I have defined a covergroup inside a package and creating instances of it in a class as shown below:

covergroup example_cg(bit en);

  option.name = "ex_cg";
  option.per_instance = 1;

  ex_cp: coverpoint en;

endcovergroup

class ex_coverage_collector extends uvm_component;

.

..

  example_cg ex_cg[4];

endclass

I am getting this error:

xmvlog: *E,CGIANS Arrays of covergroup instances are not supported

What is the best approach to create multiple covergroup without code replication?