dmusic loader question

[Rok Mandeljc]

I was planning to (properly) implement DirectMusic Loader, based on
example I've found in MSDN
(http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnmusic/htm...).

But as I don't have enough experience with COM interfaces, I got stuck
with implementing IStream interface; how does one declare interface,
which consists of two other interfaces (CMyIStream class in example code
is actually IDirectMusicGetLoader and IStream at the same time)?

BTW, is it illegal to use MSDN examples to implement stuff in wine
(EULA...)?