No it didn't say anything like that but the guy that works there said it should work
here is the link:
http://www.pbtech.co.nz/index.php?z=p&p=ITPAK246&name=DYNAMIX-STEREO-CABLE-Y-3.5mm-JACK-PLUG-2M-SPLITTER
I have a dell LATITUDE e6330 and a headset with 2 cables but the latitude only has 1 hole.
My PC also cant find the mic for some reason even though I got an adapter. But the adapter I got was really cheap so I'm not sure whether it was the adapter or the computer.