http://www.amule.org/wiki/index.php/Ed2k_links_handling#Local_handling_of_ed2k_links

Local handling of ed2k links

GNU/Linux

As a general idea, in most Linux systems, self-compiled aMules will install the ed2k utility in /usr/local/bin/ed2k, while package-installed aMules will install it in /usr/bin/ed2k. As an exception, it is known that SuSE packages install it in /usr/local/bin/ed2k.

If you have installed Debian or Ubuntu you must install "amule-utils", and "amule-ed2k" to get this way working.

Firefox 2 and 3 (or later)

Handling ED2k links in Firefox can be configured in two ways: either for an individual user, or for all users of the computer.

Configuration for a single user

• Insert about:config in the address bar

• Right click on the list, select New, then Boolean; insert network.protocol-handler.external.ed2k as Preference Name and true as Value

• Now another right click, select New and String; insert network.protocol-handler.app.ed2k as Preference Name and /path/to/ed2k (path to where the file is installed on your system) as Value.

For Firefox 3 and higher only, you should also:

• Right click on the list, select New, then Boolean; insert network.protocol-handler.expose.ed2k as Preference Name and false as Value

After that, click over an ed2k link, and Firefox should ask which
app you want to use to open the link. Choose /usr/local/bin/ed2k and it
should work.

System-wide configuration

• Having root privileges, open the file /usr/share/firefox/greprefs/all.js (or /usr/local/share/firefox/greprefs/all.js) in a text editor

• Add the following lines at the end of the file:

// ED2K link handling
pref("network.protocol-handler.external.ed2k", true);

pref("network.protocol-handler.app.ed2k", "/path/to/ed2k");

Substitute the "/path/to/ed2k" string with the program's real path.

For Firefox 3 and higher only:

• Add yet another line to the all.jsfile:

pref("network.protocol-handler.expose.ed2k", false);

After saving changes, restart the browser. After clicking over an
ed2k link, Firefox should ask which app you want to use to open the
link. Choose /usr/local/bin/ed2k and it should work.