key error in PPA repository

[Frank Zimper]

Running
   add-apt-repository --yes ppa:ts.sch.gr

results in this output

gpg: keyring `/tmp/tmpydcb25m_/secring.gpg' created
gpg: keyring `/tmp/tmpydcb25m_/pubring.gpg' created
gpg: requesting key 03AFA832 from hkp server keyserver.ubuntu.com
gpg: /tmp/tmpydcb25m_/trustdb.gpg: trustdb created
gpg: key 03AFA832: public key "\xce\x91\xcf\x80\xce\xbf\xce\xb8\xce\xb5\xcf\x84\xce\xae\xcf\x81\xce\xb9\xce\xbf \xce\xa4\xce\xb5\xcf\x87\xce\xbd\xce\xb9\xce\xba\xce\xae\xcf\x82 \xce\xa3\xcf\x84\xce\xae\xcf\x81\xce\xb9\xce\xbe\xce\xb7\xcf\x82 \xce\xa3\xce\x95\xce\xa0\xce\x95\xce\x97\xce\xa5" imported
gpg: Total number processed: 1
gpg: imported: 1 (RSA: 1)
'ascii' codec can't decode byte 0xce in position 71: ordinal not in range(128)

A subsequent apt-get update obviously complains about an unsigned repository.

[Frank Zimper (frank-frankoli)]

root's locale was set to "C"

Works fine if locale is set to "en_US.UTF-8"