help request about NX1101 (or the IP1000) network card driver

Hey List, I'm wondering if anyone else has any experience using the NX1101 Asus network card with kernel version 2.6.22? It identifies itself the following in lspci: Sundance Technology Inc / IC Plus Corp IC Plus IP1000 Family Gigabit Ethernet (rev 41) The reason that I'm asking is, that it took me quite some hours to get the module up and running. The makefile had some bugs in it, as well as the module source itself, which I needed to fix first. It's running now, but there seems to be something wrong with multicast. I'm using Linux-IGD for UPNP, and this requires multicast packets to work. However, when my clients send multicast packets to find the upnp daemon, the computer with the NX1101 doesn't pick them up. When I put the card into promiscuous mode, it does get the packets (and responds to them properly). I can't put my finger to it, a really weird problem.