COM/interface question

[Mike]

I'm getting a strange compilation error with a COM interface I'm trying to access. Here's the relevant part of the interface:

extern(Windows) interface IASIO : IUnknown
{
    ASIOBool init(void*);
[snip]
    ASIOError getChannels(long*, long*);
[snip]
}

And here's the problem:

test.init(null); // Error: function expected before (), not null of type IASIO*
test.getChannels(&ichans, &ochans); // compiles

test is of type IASIO*. ASIOBool and ASIOError are both aliases for long. The null in the "init" is not the problem; if I give the function the correct pointer it doesn't compile as well.

Has anybody any idea why one call compiles and the other doesn't?

-Mike