Unable to overload method in AIDL interface

I am unable to overload a method in the AIDL interface.

I wanted to have 2 functions with the same name but diffrent number of arguments like this:

boolean callMethod(in String pClass, in String pMethod, in String pParam);
void    callMethod(in String pClass, in String pMethod);

when I do so, I get an error saying "attempt to redefine method callMethod"

Regards,