ERROR: AttributeError('NoneType' object has no attribute 'callRemote')

[killyourtv]

Sometimes I get this with current git while repairing or uploading.

"ERROR: AttributeError('NoneType' object has no attribute 'callRemote')"
"[Failure instance: Traceback: <type 'exceptions.AttributeError'>: 'NoneType' object has no attribute 'callRemote'"
/usr/lib/pymodules/python2.7/foolscap/call.py:677:_done
/usr/lib/pymodules/python2.7/foolscap/call.py:60:complete
/usr/lib/python2.7/dist-packages/twisted/internet/defer.py:362:callback
/usr/lib/python2.7/dist-packages/twisted/internet/defer.py:458:_startRunCallbacks
--- <exception caught here> ---
/usr/lib/python2.7/dist-packages/twisted/internet/defer.py:545:_runCallbacks
$INST/tahoe-lafs/src/allmydata/immutable/upload.py:553:_got_response
$INST/tahoe-lafs/src/allmydata/immutable/upload.py:420:_loop
$INST/tahoe-lafs/src/allmydata/immutable/upload.py:105:query
        '<root>': healthy
        '<root>': healthy
        'debian': healthy
        'debian/favicon.ico': healthy
        'debian/index.html': not healthy
         repair successful
        'debian/style.css': healthy
        'debian/dists': not healthy
         repair successful
        'debian/dists/sid': not healthy
         repair successful
        'debian/dists/sid/Contents-amd64': not healthy
         repair successful
        'debian/dists/sid/Contents-amd64.bz2': healthy
        'debian/dists/sid/Contents-amd64.gz': healthy
        'debian/dists/sid/Contents-armel': healthy
        'debian/dists/sid/Contents-armel.bz2': healthy
        'debian/dists/sid/Contents-armel.gz': healthy
        'debian/dists/sid/InRelease': not healthy
         repair successful
        'debian/dists/sid/Release': healthy
        'debian/dists/sid/Release.gpg': not healthy
         repair successful
        'debian/dists/sid/main': not healthy
         repair successful
        'debian/dists/sid/main/binary-amd64': not healthy
         repair successful
        'debian/dists/sid/main/binary-amd64/Packages': not healthy
         repair successful
        'debian/dists/sid/main/binary-amd64/Packages.bz2': not healthy
         repair successful
        'debian/dists/sid/main/binary-amd64/Packages.gz': not healthy
         repair successful
        'debian/dists/sid/main/binary-amd64/Release': not healthy
         repair successful
        'debian/dists/sid/main/binary-armel': not healthy
         repair successful
        'debian/dists/sid/main/binary-armel/Packages': not healthy
         repair successful
        'debian/dists/sid/main/binary-armel/Packages.bz2': not healthy
         repair successful
        'debian/dists/sid/main/binary-armel/Packages.gz': not healthy
         repair successful
        'debian/dists/sid/main/binary-armel/Release': not healthy
         repair successful
        'debian/dists/sid/main/binary-i386': healthy
        'debian/dists/sid/main/binary-i386/Packages': not healthy
         repair successful

There's nothing unusual in twistd.log, and I've been AFK when it has occurred, so I don't have any incident reports.

allmydata-tahoe: 1.9.0.post134.dev0,
foolscap: 0.6.3,
pycryptopp: 0.6.0.1206569328141510525648634803928199668821045408958,
zfec: 1.4.24,
Twisted: 11.1.0,
Nevow: 0.10.0,
zope.interface: unknown,
python: 2.7.3rc2,
platform: Linux-debian_wheezy/sid-x86_64-64bit_ELF,
pyOpenSSL: 0.13,
simplejson: 2.5.0,
pycrypto: 2.5,
pyasn1: unknown,
mock: 0.8.0,
sqlite3: 2.6.0 [sqlite 3.7.11],
setuptools: 0.6c16dev3