I've been trying to dial from the address book using click to dial,
facilitated by the TBDialOut 1.7.2 plugin, which converts the address
book phone numbers into URIs.

I already have sipdialer installed and configured and it works from the
command line if I type /usr/bin/sipdialer $NUMBER

I added tel:  into gconftool as documented in the sipdialer README:

gconftool-2 -t string \
   -s /desktop/gnome/url-handlers/$scheme/command "/usr/bin/sipdialer %s"
  gconftool-2 -t bool \
   -s /desktop/gnome/url-handlers/$scheme/needs_terminal false
  gconftool-2 -t bool \
   -s /desktop/gnome/url-handlers/$scheme/enabled true


and I can query the values from sipdialer.

The icedove address book displays the phone numbers as clickable tel: links

When I click one, I get the message "tel is not a registered protocol"

I went into the config editor and tried adding the following, which
should not be necessary given the gconf settings exist:

network.protocol-handler.app.tel (string) = /usr/bin/sipdialer
network.protocol-handler.external.tel (bool) = true
network.protocol-handler.expose.tel (bool) = true

and tried again and I still get the same error.

I just upgraded from 17.0.10-1~deb7u1 to 24.4.0-1~deb7u1 on wheezy

The problem still exists



I found some links related to this issue:

http://www.codepad.de/en/software/firefox-add-ons/telify.html?start=3
- this has notes about the "sip:" protocol rather than "tel:"


https://bugzilla.mozilla.org/show_bug.cgi?id=173010
- this observes that some protocols are blocked for safety reasons, but
I would hope that the manual settings I created in icedove preferences
would override such default behavior


http://kb.mozillazine.org/Register_protocol


http://www.oak-wood.co.uk/faq/content/5/14/en/how-do-i-register-a-url-handler-for-the-sip-protocol-in-gnome-_-ubuntu.html

I had a look at this too:

http://kb.mozillazine.org/Network.protocol-handler.app.%28protocol%29


It really isn't clear how to enable "tel" URIs either using a command
defined within icedove or using the desktop/gnome settings.

Hello Daniel,

I'm not a expert in this part, especially in protocol handling.
But if we implement this we have to take care for all the none Gnome
users.

It seems to me that there is on extension that will do the most of the
integration inside Thunderbird/Icedove.

https://addons.mozilla.org/de/thunderbird/addon/telify/

I found a thread on the Ubunto forum that shows how to integrate the
Jitsi program to use SIP numbers.

http://ubuntuforums.org/showthread.php?t=2181012

For me it's unclear how to define the standard application for SIP
handling for the user without manuall edit some files inside the system.

But as you are a "enhanced" user you can test the steps from the thread
in the Ubuntu forum.

Regards
Carsten

I tested in stretch, details in this comment:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=746707#73

It looks like the situation has improved with Thunderbird 1:45.8.0-3
 (using xul-ext-tbdialout 1.7.2-1)