AD authentication OD Mobile Account 10.6.2

We are in the process of moving over to having all users log into their macs using their existing windows username rather than having two seperate user directories as it currently stands. The process we wish to achieve is the user to be authenticated by the AD directory when logging in and their home folder to be a mobile account with synchronisation which resides on the Mac servers.From various posts I gather that this is possible without extending the AD Schema to incorporate apple objects The steps we have taken so far are: I have bound our OD Master to AD Bound a test client to AD and OD (OD first in search path) unticking use UNC path and unticking create mobile account at login. Created a computer group on the master Added ManagedClient to preferences In the details tab I have modified the "Mobile Account & Other Options" to include the following "Create Mobile Account" "True" "Create Portable Home Directory" "True" "Mobile Home Location" "path" "Mobile Home Parent Path" "/Network/Servers/our-server.com/Volumes/DATADRIVE/Home" "Synchronisation URL" "afp://our-server.com/Home/%@" No problems with authentication but when logging on with the client and "ad_username" I get the error "Unable to create Mobile account" There was a problem while creating or accessing "/Network/Servers/our-server.com/Volumes/DATADRIVE/Home/ad_username" The path is accessible from the client in terminal, initially I thought it was a permissions issue and gave the user write permissions to the share, just to test but that made no difference. Is there something Im missing here, any tips would be gratefully recieved!