I found this on another thread - an easier way to do it, once you have jeanettes skin as your vampire's skin, is just to change a few names apparently
Extract the clandoc000.txt file from the Vdata/system/ (it's located inside one of the packs, can't remember which sorry!)
Open it and change the following lines:
"F_Body0" "models/character/pc/female/malkavian/armor0/malkavian_Female_Armor_0.mdl"
"F_Body1" "models/character/pc/female/malkavian/armor1/malkavian_Female_Armor_1.mdl"
"F_Body2" "models/character/pc/female/malkavian/armor2/malkavian_Female_Armor_2.mdl"
"F_Body3" "models/character/pc/female/malkavian/armor3/malkavian_Female_Armor_3.mdl"
"F_Body4" "models/character/pc/female/malkavian/armor4/malkavian_Female_Armor_3.mdl"
"F_Body5" "models/character/pc/female/malkavian/armor5/malkavian_Female_Armor_3.mdl"
to:
"F_Body0" "models/character/npc/unique/santa_monica/Jeanette/Jeanette.mdl"
Edit: Forgot, if u want to change the appearance of a clan(other than Malk, ex toreador, goto the lines with female/toreador/ instead.)
This method is easier and it will make ur character able to frenzy, EVEN with a changed skin.
Edit: I also came across this link, which may help:
http://home.earthlink.net/~jdhibberd/vamp/pctonpc.html