Comment 8 for bug 1061101

I also caught the bug when try:
apt-add-repository ppa:pandora-net/ppa

You are about to add the following PPA to your system:
 P2P social network Pandora
 More info: https://launchpad.net/~pandora-net/+archive/ppa
Press [ENTER] to continue or ctrl-c to cancel adding it

Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 551, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/dist-packages/softwareproperties/ppa.py", line 99, in run
    self.add_ppa_signing_key(self.ppa_path)
  File "/usr/lib/python2.7/dist-packages/softwareproperties/ppa.py", line 127, in add_ppa_signing_key
    if len(signing_key_fingerprint) < 160/8:
TypeError: object of type 'NoneType' has no len()

What's wrong?