This is in reference to the problem Tom Brown reported that on older platforms we're still having unicode problems -- though we already had them addressed for EL 5 and Fedora.
http://git.fedorahosted.org/git/cobbler?p=cobbler;a=commitdiff;h=f8be727262a...
This will be included in 1.6.5. The general plan is to release 1.6.5 approximately one week from now, giving us some time to pick up other fixes if required.
So far this patch is of interest to you if you are running the cobbler server on EL 4, and otherwise is not important.
The basics are that this version will convert json files back down to PyYAML and use PyYAML on python versions 2.3 and before, and will use json (which is ~300x faster) on python 2.4 and above.
Extra testing is much appreciated.
For performance reasons, yes, this does mean that it is much preferred that you run Cobbler on at least EL 5. We'll continue to support Cobbler on EL 4, though it will just not be as efficient if you have a very large number of system records in it (i.e 500-1000+). If you are running those configs, definitely look into upgrading.
This is on the master branch now, and I'm in the process of applying it to devel.
--Michael