Firewalls to route between Backup, MPLS and internet traffic

We have ASA 5505. Is it possible to Port map two public IP from ADSL connection to Internal network. We already have one IP mapped.

we have VPN Site to Site access implemented ,However some of our staff cannot access the server from branch office to main office. What could be the problems

Can any one help me in configuring thhis. I would like to get configuration for both sides

I am trying to uplink between 3com switch and cisco using Gigabit modules of 3com and cisco. Do I need to enable trunking for this uplink or just plug and play will be fine. Also 3 com speed is 100 Mbps So whats configuration used in cisco 2960 switc...