Collect doesn't work with mp

[dmakhno]

$ pip show nose2

Metadata-Version: 1.1
Name: nose2
Version: 0.6.5

$ uname -a
Darwin local 14.5.0 Darwin Kernel Version 14.5.0: Thu Apr 21 20:40:54 PDT 2016; root:xnu-2782.50.3~1/RELEASE_X86_64 x86_64

config

[unittest]
plugins = nose2.plugins.collect
          nose2.plugins.mp


[multiprocess]
always-on = True
processes = 8

[collect-only]
always-on = True

running
nose2 -v -c unittest.cfg -s my_tests

Under debug I see that CollectOnly.startTestRun is called earlier than CollectOnly.registerInSubprocess as results tests are not collected and have normal run.
CollectOnly.startSubprocess is never called.
I'm new in nose2 and don't know is it real reason and the issue or I'm doing something wrong.