Well WRVS4400n is a linksys box, with very less funcationality , you can configure the vpn using following link-------
http://www.ergotron.com/Portals/0/tp/g/oem/WRVS4400N_V2_User_Guide.pdf
Please refer VPN session under "Setting up and configuring the router"
Please not split tunnel functionallity will not be possible as its a basic box.
You can use Cisco ASA 5505 or 5510 to have a vpn tunnel and use of the internet connection off that box.
Hope that answers your question.
Thanks
Ankur