Ethernet Problems - National Semiconductor DP83815/16

Using Knoppix 4.2 and it's loaded fine on my server. Able to configure the Ethernet interface and ran "lsmod" and verified the native driver "natsemi.ko" was loaded. I'm able to transmit just fine, but every receive packet back into the server is being dropped? I'm wondering if anyone else is having problems with the National Semiconductor DP83815/16 controller? Is anyone else sucessfully using this Ethernet controller?

I've tried several other Linux operating systems based off Knoppix (DSL & DSL-N) and encouter the same problem with dropped receive packets.

Thanks,
John

Does anyone have the source code for the DP83815/16 Ethernet driver?