Scrap what I previously said
I see that was commited on the 14th April, 1.71 was released on the 2nd April.
Just tested with that iPlugin in the prototype, that was also returning fine for me. If its still not working for you the only thing you can do is get hold of 1.75 in CVS and also delay your plugin release until this super version is out
Either way its not an issue for the upcoming build of AMXX 1.75