won't launch external editor

Running with node.js 0.4.2 on Ubuntu 10.04. The server looks like it's working correctly:

jacob@jacob-laptop:~$ textareaserver --editor-cmd gedit
8 Mar 11:36:32 - socket.io ready - accepting connections
TextareaServer is running at 127.0.0.1:32942
8 Mar 11:36:37 - Initializing client with transport "websocket"
8 Mar 11:36:37 - Client 1310008275322616 connected

background.html also does not report any error.

Unfortunately, right-clicking a text area, and choosing "Edit in external editor" does not appear to have any effect - no editor window opens. I've tried using a different editor command, e.g. "textareaserver --editor-cmd gvim", but this likewise did not have any effect.

Verbose debugging output would be useful in understanding why this might not be working.