During Tomcat startup the JDK is disqualified with the following message:
Dec 8, 2010 1:06:25 AM org.apache.catalina.core.StandardContext listenerStart
SEVERE: Exception sending context initialized event to listener instance of class org.opennms.web.DependencyCheckingContextListener
java.lang.RuntimeException: System property 'java.vm.name' does not contain a suitable JVM signature ('OpenJDK 64-Bit Server VM'). OpenNMS recommends the official Sun JVM. You can edit /opt/opennms/webapps/opennms/WEB-INF/web.xml and change the value for the 'dontBlameOpenNMS' context parameter from 'false' to 'true', but don't blame OpenNMS for any errors that occur without switching back to a supported JVM and setting the property back to 'false', first.
at org.opennms.web.DependencyCheckingContextListener.logAndOrDie(DependencyCheckingContextListener.java:102)
at org.opennms.web.DependencyCheckingContextListener.checkJvmName(DependencyCheckingContextListener.java:86)
at org.opennms.web.DependencyCheckingContextListener.contextInitialized(DependencyCheckingContextListener.java:63)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3972)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4467)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:526)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:637)
at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:563)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:498)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1277)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:321)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:722)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
at org.apache.catalina.core.StandardService.start(StandardService.java:516)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
at org.apache.catalina.startup.Catalina.start(Catalina.java:593)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Dec 8, 2010 1:06:25 AM org.apache.catalina.core.ApplicationContext log
INFO: Initializing Spring root WebApplicationContext

During installation runjava reported:
runjava: Looking for an appropriate JRE...
runjava: Checking for an appropriate JRE in JAVA_HOME...
runjava: found: "/usr/lib64/jvm/java/bin/java" is an appropriate JRE

Output from java -version:
java version "1.6.0_20"
OpenJDK Runtime Environment (IcedTea6 1.9.2) (suse-0.2.1-x86_64)
OpenJDK 64-Bit Server VM (build 17.0-b16, mixed mode)