PAC AUX-BOX equivalent for a Nissan?

Hi,

I'm looking for an adaptor to plug my MP3 player in the head unit of my car. My car is an Altima GXE bought in Canada in 1999. The head unit as CN698 as a front panel ID. I haven't gotten the head unit out yet, so I don't know the exact model.

For some reason, Nissan is the only maker I can't find an adaptor to convert the pinout for the optional CD-charger (I don't have one) to two RCA cables.

For example, I found the PAC AUX-BOX which seems to work on every make of car except the Nissan :-\

Thanks in advance for your help.

Carl