possible bug: yum and rhn-plugin interaction

I might have found a bug that is triggered when I:
- use RHEL5.4
- use yum 3.2.25 (not really sure when it first occur though)
- have yum-rhn-plugin-0.5.4-13.el5, with valid redhat subscription

The symptom is that simple operations like "yum list yum" failed with
something like

  File "/usr/lib/python2.4/site-packages/yum/yumRepo.py", line 1561,
in _retrieveMD
    size=thisdata.size)

The simple workaround is to remove "size=" parameters to calls to
self._getFile in yumRepo.py.

The bug does not happen (i.e. "yum list yum" works just fine with
unmodified yum 3.2.25) if you don't have a valid redhat subscription,
or if you disable rhn-plugin manually.

Should I file this in bugzilla? If so, what category, yum or yum-rhn-plugin?

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