Description of problem:

rhn_check does not install scheduled updates, reports completion
up2date debug reports "More recent version of package .. is already installed" for all packages.

Version

We "just" upgraded from Spacewalk 2.2 to 2.4 and therefore from 
yum-rhn-plugin-2.2.7-1.el5
to
yum-rhn-plugin-2.4.6-1.el5

How to reproduce:

1. stop osad (to debug)
2. install yum-rhn-plugin-2.4.6-1.el5 on a Centos 5
3. schedule a package upgrade using spacewalk gui
4. execute rhn_check -vvv

Actual results:

package ist not updated
[Thu Nov 12 14:50:34 2015] up2date D: More recent version of package kpartx-0:0.4.7-64.el5_11.x86_64 is already installed

Expected results:

update of package

Additional info:

we have 164 affected systems it seems to be not node specific
works again when downgrading yum-rhn-plugin to 2.2.7-1.el5 

it looks like the compare function in /usr/share/rhn/actions/packages.py around line 347 does no longer work as expected. (at that point we stopped debugging)