GNOME_KEYRING_RESULT_IO_ERROR from launchpadlib

I have no reliable way to reproduce it, but every now and then when using pull-ppa-source (from lp:kubuntu-dev-tools) the script fails with this error: (tokens stripped from output)

Gkr-Message: received an invalid, unencryptable, or non-utf8 secret
Gkr-Message: call to daemon returned an invalid response: (null).(null)()
Gkr-Message: received an invalid, unencryptable, or non-utf8 secret
Gkr-Message: call to daemon returned an invalid response: (null).(null)()
The authorization page:
 (https://launchpad.net/+authorize-token?oauth_token=<>&allow_permission=DESKTOP_INTEGRATION)
should be opening in your browser. Use your browser to authorize
this program to access Launchpad on your behalf.
Press any key to continue or wait (5) seconds...
Waiting to hear from Launchpad about your decision...
00:24:38 unnamed app(24933) ClientApp::doIt: Creating ClientApp
00:24:38 kioclient(24933) ClientApp::kde_open: KUrl("https://launchpad.net/+authorize-token?oauth_token=<>&allow_permission=DESKTOP_INTEGRATION")
00:24:38 kioclient(24933)/kio (KRun) KRun::slotTimeout: KRun(0x269dbe0) slotTimeout called
00:24:38 kioclient(24933)/kio (KRun) KRun::init: INIT called
00:24:38 kioclient(24933)/kdecore (KSycoca) KSycocaPrivate::openDatabase: Trying to open ksycoca from "/var/tmp/kdecache-yofel/ksycoca4"
00:24:38 kioclient(24933)/kfile (kdelibs) KRecentDocument::add: KRecentDocument::add for "https://launchpad.net/+authorize-token?oauth_token=<>&allow_permission=DESKTOP_INT
EGRATION"
00:24:38 kioclient(24933)/kio (KRun) runTempService: runTempService: first url "https://launchpad.net/+authorize-token?oauth_token=<>&allow_permission=DESKTOP_INTEGRATION"
00:24:38 kioclient(24933)/kio (KRun) supportedProtocols: supportedProtocols: ("KIO")
00:24:38 kioclient(24933)/kio (KRun) runTempService: runTempService: KProcess args= ("/usr/bin/firefox", "https://launchpad.net/+authorize-token?oauth_token=<>&allow_permiss
ion=DESKTOP_INTEGRATION")
00:24:38 kioclient(24933)/kdecore (KStartupInfo) KStartupInfo::createNewStartupId: creating: "yofel-T510;1378506278;233618;24933_TIME0" : ""
00:24:38 kioclient(24933)/kdecore (KStartupInfo) KStartupInfo::sendStartup: sending "new: ID="yofel-T510;1378506278;233618;24933_TIME0" BIN="firefox" DESCRIPTION="Launching " DESKTOP=1 WM
CLASS="0" HOSTNAME=yofel-T510 NAME="firefox" SCREEN=0"
00:24:38 kioclient(24933)/kdecore (KStartupInfo) KStartupInfo::sendChange: sending "change: ID="yofel-T510;1378506278;233618;24933_TIME0" PID=24935"
00:24:38 kioclient(24933)/kio (KRun) KRun::slotTimeout: KRun(0x269dbe0) slotTimeout called

(process:24935): GLib-CRITICAL **: g_slice_set_config: assertion 'sys_page_size == 0' failed
Gtk-Message: Failed to load module "canberra-gtk-module"
Gtk-Message: Failed to load module "canberra-gtk-module"
00:24:38 kioclient(24933)/kio (KRun) KProcessRunner::slotProcessExited: "firefox" exitCode= 0 exitStatus= 0
00:24:38 kioclient(24933)/kdecore (KStartupInfo) KStartupInfo::sendFinish: sending "remove: ID="yofel-T510;1378506278;233618;24933_TIME0" HOSTNAME=yofel-T510 PID=24935"
Gkr-Message: secret service operation failed: The secret was transferred or encrypted in an invalid way.
Traceback (most recent call last):
  File "/usr/bin/pull-ppa-source", line 49, in <module>
    lp = Launchpad.login_with("pull-ppa-source", "production")
  File "/usr/lib/python2.7/dist-packages/launchpadlib/launchpad.py", line 539, in login_with
    credential_save_failed, version)
  File "/usr/lib/python2.7/dist-packages/launchpadlib/launchpad.py", line 346, in _authorize_token_and_login
    credentials = authorization_engine(credentials, credential_store)
  File "/usr/lib/python2.7/dist-packages/launchpadlib/credentials.py", line 520, in __call__
    credential_store.save(credentials, self.unique_consumer_id)
  File "/usr/lib/python2.7/dist-packages/launchpadlib/credentials.py", line 276, in save
    raise e
keyring.errors.PasswordSetError: GNOME_KEYRING_RESULT_IO_ERROR

Happens usually when using the kubuntu ppa packages batch backport script which calls pull-ppa-source about 160 times (once for every KDE SC source).

ProblemType: BugDistroRelease: Ubuntu 13.10
Package: gnome-keyring 3.8.2-0ubuntu3
ProcVersionSignature: Ubuntu 3.11.0-4.9-generic 3.11.0-rc7
Uname: Linux 3.11.0-4-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.12.1-0ubuntu3
Architecture: amd64
Date: Sat Sep 7 00:27:19 2013
EcryptfsInUse: Yes
InstallationDate: Installed on 2011-10-08 (699 days ago)
InstallationMedia: Kubuntu 11.10 "Oneiric Ocelot" - Beta amd64 (20111007)
MarkForUpload: TrueSourcePackage: gnome-keyring
UpgradeStatus: No upgrade log present (probably fresh install)