python-dateutil will be updated to version 2.x and there may be changes that affect this package. If nagios-plugins-lcgdm will work with the newer python-dateutil, you can safely close this bug. If nagios-plugins-lcgdm really does require python-dateutil 1.5, please use Requires: python-dateutil15 for Fedora versions of the package until it can be updated.
Checked with python-dateutil 2.4.0, the probe that uses dateutil is only check_hostcert, and it runs fine.