Tvheadend

Hi All,

I've been researching here and around for a while, but I couldn't;t find an exact answer.
Bit of scenario, first. I have XBMCbuntu running on a PC with TVHEADEND installed as backend and a DVB-T USB adapter for DTT channels. Everything works OK, I can watch DTT channels via LIVETV connecting on TVHEADEND backend server (127.0.0.1, obviously).
Now, I also have a Dreambox 500 for satellite channels, running CCCam to decrypt channels with a legitimate card I subscribed (Italian TVSAT).
Since I can't connect (besides tuxbox) my XBMC to the DM500, I'm thinking to buy a DVB-S usb adapter (no room for a PCI card) to combine in TVHEADEND to consolidate both DTT and SAT channels.
here's the thing. I have a USB card reader installed on XBMCbuntu, which is correctly seen by the system and also recognize my TVSAT card.
I was wondering if anyone has a similar configuration, and if it's possible to have sat channels fed by the DVB-S usb device decrypted used the card reader and the card I have (using cccam with tvheadend, perhaps?). I'd like to know before buying any DVB-S or (better) DVB-S2 usb device :-)
Any help would be much appreciated.
My apologies in the first place if this thread has already been discussed, but I couldn't find any. If this is the case, can anyone direct me to the right thread?

Ciao!