Hi liudr,
Just ckecked the schematics (arduino-ethernet-shield-05-schematic.pdf), I get is this
J1-3 -> SS -> D2
J2-1 -> WP -> A0
J2-2 -> DETECT -> A1
J3-3 -> PD2 -> D10
J3-5 -> SD_CS -> D12
ISP-1 (J3-5) -> MISO -> D12
ISP-3 (J3-6) -> SCK -> D13
ISP-4 (J3-4) -> MOSI -> D11
I don't see them using D4 (I assume by pin 4 you mean digital 4)
What I don't understand is the two highlighted signals. They get MISO from the ISP header, but on the Arduino that's connected directly to J3-5 which they also use for SD_CS. Qué ???
So although these signals do different things on the shield they are connected together on the Arduino.
MISO and SD_CS are electrically the same, so how can the SD card's data output also be it's chip select? :-/
Have I missinterpreted something here?
Rob (confused)
EDIT: Just checked this against shieldlist.org, and it matches.