problem adding a PPA

i've recently downloaded Trisquel 6.0.1 and I'm having problems when trying to add any PPA. anyone knows how can i fix it?

andre@andre-300E4C-300E5C-300E7C:~$ sudo add-apt-repository ppa:gezakovacs/ppa
[sudo] password for andre:
You are about to add the following PPA to your system:
UNetbootin http://unetbootin.sourceforge.net/ is a cross-platform utility that can create Live USB systems and can load a variety of system utilities or install various Linux distributions and other operating systems without a CD.

Homepage: http://unetbootin.sourceforge.net/
Wiki: http://unetbootin.wiki.sourceforge.net/
Downloads: http://sourceforge.net/project/showfiles.php?group_id=222386
Sourceforge: http://sourceforge.net/projects/unetbootin
Launchpad: http://launchpad.net/unetbootin

More info: https://launchpad.net/~gezakovacs/+archive/ppa
Press [ENTER] to continue or ctrl-c to cancel adding it

Traceback (most recent call last):
File "/usr/bin/add-apt-repository", line 185, in
sp = SoftwareProperties(options=options)
File "/usr/lib/python2.7/dist-packages/softwareproperties/SoftwareProperties.py", line 97, in __init__
self.reload_sourceslist()
File "/usr/lib/python2.7/dist-packages/softwareproperties/SoftwareProperties.py", line 585, in reload_sourceslist
self.distro.get_sources(self.sourceslist)
File "/usr/lib/python2.7/dist-packages/aptsources/distro.py", line 87, in get_sources
raise NoDistroTemplateException("Error: could not find a "
aptsources.distro.NoDistroTemplateException: Error: could not find a distribution template