ip filtering

Hi guys!

I am developing an mail filter application. I used Packet32.sys and Packet32.dll given in the Microsoft DDK for NT 4.0. I could read the packets from the Network card using packet32.dll(it is statically linked to my application). I could not remove the packets from NIC(network interface card)i.e., i am only getting a copy of the packet. This functionality is required to filter and redirect the packets. Is there any NDIS function to discard the packet at NIC? Should I have make changes in the driver source code?

Any one know the answer, Please let me know.

This is very crucial for my project.

regards
ramji