Debian Kde Iceweasel/Firefox: setting custom protocols handlers

I recently switched from Ubuntu 10.04 gnome to Debian wheezy Kde.

Everything's work fine, except to the Iceweasel/firefox custom protocols!

I added komodo.protocol in my ~/.kde/share/services with:

[Protocol]
exec=python /path/to/my/script.py "%u"
protocol=komodo
input=none
output=none
helper=true
listing=
reading=false
writing=false
makedir=false
deleting=false

This works for chrom(e|ium), but not for firefox.

I've read about firefox should use the gnome configs even under Kde, so I tried:

gconftool-2 -s /desktop/gnome/url-handlers/komodo/enabled --type Boolean true
gconftool-2 -s /desktop/gnome/url-handlers/komodo/command 'python /path/to/my/script.py %s' --type String

that used to work when I was on ubuntu, but it doesn't on kde.

Any idea?

EDIT

An example link: komodo:/var/www/app/0/Modules/Controller/Node/Controller_Node.class.php:1202

And if I run the command komodo /var/www/app/0/Modules/Controller/Node/Controller_Node.class.php:1202 from the terminal it works correctly; my python script simply check few things and then runs this command – but with firefox/iceweasel it never gets triggered.