There are properties in the AMConfig.properties file that affect logging output:
This property will enable or disable logging. The default is ACTIVE.
service is the service's normal log file name. For example, to specify a logging level for amSAML.access, use the property iplanet-am-logging.amSAML.access.level.level is one of the java.util.logging.Level values and denotes the level of detail recorded in the log file. The levels are OFF, SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST, and ALL. Most services do not record log levels with higher detail than INFO.