Regarding data exchange between Matlab and COM server

Dear all, I have a problem with data exchange with COM server. I created COM server using the following command; COMSERV = feval('actxserver', 'ProgID');

Now, I would like to read VARIANT from the other program, manipulate it then send it back to the other program. Each time I try to send back the new values, I receive the following error;

Invoke Error, Dispatch Exception: Unspecified error

What I understand that Matlab converts the received values from COM server from variant to double. I believe that the problem origins from trying to send double variable to the other program which expects a variant.

My question is how can I send the double data from Matlab to the other program in Variant type. Is there a way to force Matlab to convert back the double into variant. If you feel that this is not the problem, would you please suggest what might be the cause of such problem.

Thanks in advance