port concatenation during instantiation inside constructor

Hi,

I have three modules A,B and C. I want to integrate these three modules inside TOP module constructor.

Now module A has one port sc_out<<sc_uint<2> > out;

       module B has one port sc_out<<sc_uint<2> > out;

       module C has one port sc_in<<sc_uint<4> > in;

Now inside TOP constructor I have instantiated all these three modules A,B and C. And during connection I am doing following-

A_inst->out(out1);

B_inst->out(out2);

C_inst->in((out2,out1));

out1 and out2 both are sc_signal<sc_uint<2> > ;

This is throwing error that concatenation at ports not possible. Is it I am doing something wrong? How to perform these port concatenation directly inside constructor without introducing separate SC_METHOD for that?

Regards,

Anindya