After Enabeling log Accounting ON TMG server Forme NAP Console to log VPN client connection Propertise In The Client_IP_Address filed it shows TMG Ip address Insted of Client Machin Ip address

hi

I have TMG server with Nap service and sql service install on it,I have vpn client who connect to Internet Via vpn connection from my Internal network.I want to enable Accounting that report which client frome which computer start vpn connection.

after config and enable log accounting from nap console which save record on sql databse  ,it creat the databse ,but when i query the databse in (Client_IP_Address) filed insted of real client machine ip address is show me the TMG ip address .

there is a log file (IN*) in c:\windows\system32\report\  folder which show me the vpn machin client ip address and user propertise connection correctly.

I print screen the Database and select the problem.

you will be kind enough if you help me.