It will flush to the keyserver (d.net, Mika, or whatever else is specified) and will use remote buffers AS LONG AS it has permissions to access the remote directory. If the client is running on a Win9X machine and the remote drive is shared with a password or on an NT machine it probably won't. However if the client is running on an NT machine, you can choose a username and password that the Distributed.net client service will run under. That would allow it to access the remote directory.
"You had me at Meat Tornado." -- "I was born ready. I'm Ron f***ing Swanson."