If you install QueueMetrics on a recent Fedora, the package "mysql-connector-java" has the same name but it's not the same thing as the package that comes from Loway repositories. This makes the installation seem to be OK but QM will complain that the MySQL connector keeps on being missing.
In order to solve the issue, you should issue the following commands:
yum remove mysql-connector-java.i386
if Qm was already installed (this will remove Qm as well).
If Qm was never installed or just removed, you can install the correct one by typing:
yum install mysql-connector-java.noarch
yum install queuemetrics
At this point you'll have the correct connector and QM will work.