The Birnam Wood (Episode 602)
First Aired: Wednesday, 27th October, 2004
Writer: John Wells
Director: Alex Graves

Not a Josh and Donna scene, but still very telling on Josh's part.

Yeah, I Think The Professional Term Is "Wanker"
Bullpen. Josh returns from Germany.

CAROL: CJ? I've got you booked on Meet the Press, Crossfire and Taylor Reid.
CJ: Taylor Reid?
CAROL: Nobody else would do it.
JOSH: (approaching them from behind) Now that's good staff work. Hey.
CJ: Hey. (Josh buries his face in her shoulder in a long, comforting hug) How's Donna?
JOSH: She threw me out. Her mother's driving her crazy and her IRA boyfriend is plotting sedition--or maybe it was seduction. Probably both.
CJ: The dashing photojournalist?
JOSH: Yeah, I think the professional term is "wanker".
CJ: Listen to you. Too much BBC.
JOSH: Too much sauerbraten. So, Leo's still down here?
CJ: Yeah, he's in his office.
JOSH: Why isn't he down at Camp David?

Another non-Josh-and-Donna-but-still-very-telling-on-Josh's-part scene.

It's Morning Over There Already
Camp David, night. Kate attempts to talk to a clearly pre-occupied Josh--during the entire conversation, he tries and retries to dial a number on his mobile phone.

KATE: Cell phone service sucks up here.
JOSH: Yeah, not many good spots. This is usually one of them.
KATE: Who are you trying to call at 2 in the morning? Someone you hate, I hope.
JOSH: Germany. It's morning over there already.
KATE: Your assistant doing better?
JOSH: She may fly back on Wednesday.

Many thanks to The West Wing Collection for the wonderful screencaps!