How is it connected to the net? What type of internet do you have? Do you get a public IP? Is the IP then applied to the dreambox?
If the above is true, then yes, you could share, but you really don't want to have an unsecured DM on a public IP. For €30 you could have a cheapo router which would do all you need.
Gentoo Linux - Nexus-s, Linux VDR - 2 x ATSC HD cards, Hauppauge PVR 500 for analog US Cable, 3 x Hauppauge MVP's running Vomp on VDR, UK TV on IPTV.
Not a single sat dish at the moment. :-(