Tomcat logs warning about Context/Realm property 'debug'

The following warning is logged during startup of the archetype project:

[WARNING] [talledLocalContainer] WARNING: [SetPropertiesRule]

Setting property 'debug' to '0' did not find a matching property.

Steps to reproduce:
1. svn co https://svn.onehippo.org/repos/hippo/hippo-cms7/archetypes/trunk archetype
2. cd archetype
3. mvn clean install
4. mvn -Pcargo.run

Expected: no warnings are logged in the console from which the project is started
Actual: the warning described above is logged