python-dateutil will be updated to version 2.x and there may be changes that affect this package. If python-gertty will work with the newer python-dateutil, you can safely close this bug. If python-gertty really does require python-dateutil 1.5, please use Requires: python-dateutil15 for Fedora versions of the package until it can be updated.
This package only calls dateutil.parse.parse() on dates received from remote, it should be happy with any version of dateutil.