I dont exactly know what bluetooth being classed as e38 means, but I can tell you that every BMW chasis is given a code name when it is a protype all the way through production. For example the current new3 series is labeled e90, the current 5 series is e60. The e38 is the previous generation 7 series, from 1997-2002 I believe. Id ont know if the E38 on your bluetooth classification means the chasis or not, but that is the extent of my knowledge ont he subject.
Maybe the bluetooth means it is supposed to work in that previous generation 7 series. I think you may need to contact BMW over this specifically.
1995 BMW M3 Turbo - Dakar/Black