Srini,
Below is the URL that has information on Using NAT and PAT Statements on the Cisco Secure PIX Firewall
http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_tech_note09186a00800b6e1a.shtml
Also, can you be more specific on what you want to achieve with the VPN Client Software. Do you want to terminate the VPN Client on the Pix firewall or have VPN Client users behind the Pix 506 access a VPN Server outside the Pix.
Regards,
Arul
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