At Fri, 06 May 2011 22:03:57 -0500,
Rafael wrote:
> 
> 
> Hi!
> 
> Has anybody been succesful in using the tutorial 
> http://orgmode.org/worg/org-contrib/org-protocol.html
> in the setting described in the subject (Firefox 4, Ubuntu 11.04)?
>
> […]

Apparently they changed the way this works. You need to add a
org-protocol.desktop file to ~/.local/share/applications

  [Desktop Entry]
  Name=org-protocol
  Exec=emacsclient %u
  Type=Application
  Terminal=false
  Categories=System;
  MimeType=x-scheme-handler/org-protocol;

Then run:

  $ update-desktop-database .local/share/applications/

For some reason I cannot get the bookmarklets to work, however. But
opening an org-protocol:/ URL directly works.

best, Erik