[amibroker] function() - optional parameters?

[rise_t575]

Just wondering if it is possible to use optional parameters in the function() 
function (no pun intended...), e. g.

function Test ( a, b, c, optionalD, optionalE );

Would the function call

Test( 1, 2, 3 );

generally work in this case?

I've tried it, but something doesn't seem to work correctly - so I want to make 
sure that this is generally possible.

Thanks in advance!