Disappointing inflexibility of argument passing with "alias this"

[Carl Sturtivant via Digitalmars-d]

struct Test { int i; alias i this; }
auto testFunct( Test i){ }

void main() {
     Test t;
     t = 1;
     testFunct( 1);
}


The assignment is fine, but the call is rejected by dmd.

See also
http://forum.dlang.org/post/fqfonkcdcjuwbaacqshe@forum.dlang.org