(non-)extern(C) function parameter vs templates

["Luís]

This works:

     extern(C) alias F = void function();
               alias G = void function();

     void foo(F f) {}
     void foo(G g) {}

Indeed, the correct foo is called, depending on whether the 
passed function is extern(C) or not (although I must say that the 
syntax for declaring the alias F is not good, IMO; the extern(C) 
should come after the equal sign).

Yet, the following does not work:

     void foo(T)(F f) {}
     void foo(G g) {}

     Error: function foo conflicts with template foo(T)(F f).

or

     void foo(F f) {}
     void foo(T)(G g) {}

     Error: template foo(T)(E e) conflicts with function foo.

It this not incoherent? If non-templated functions can overload 
on extern(C)/non-extern(C) function parameter, why can't 
templated functions?