Exception deleting user when User-token feature is not enabled

2014-09-11 18:32:55,611+0100 ERROR [qtp357251045-230] admin com.google.common.eventbus.EventBus.default - Could not dispatch event: com.sonatype.nexus.usertoken.plugin.internal.UserTokenEventInspector@41df9bb6 to public void com.sonatype.nexus.usertoken.plugin.internal.UserTokenEventInspector.inspect(org.sonatype.security.events.UserPrincipalsExpired)
java.lang.IllegalStateException: User-token feature is not enabled
	at com.google.common.base.Preconditions.checkState(Preconditions.java:176) [com.google.guava:16.0.1]
	at com.sonatype.nexus.usertoken.plugin.internal.UserTokenServiceImpl.ensureEnabled(UserTokenServiceImpl.java:172) [na:na]
	at com.sonatype.nexus.usertoken.plugin.internal.UserTokenServiceImpl.remove(UserTokenServiceImpl.java:362) [na:na]
	at com.sonatype.nexus.usertoken.plugin.internal.UserTokenEventInspector.handle(UserTokenEventInspector.java:52) [na:na]
	at com.sonatype.nexus.usertoken.plugin.internal.UserTokenEventInspector.inspect(UserTokenEventInspector.java:46) [na:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [na:1.7.0_51]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [na:1.7.0_51]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [na:1.7.0_51]
	at java.lang.reflect.Method.invoke(Method.java:606) [na:1.7.0_51]
	at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74) [com.google.guava:16.0.1]
	at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322) [com.google.guava:16.0.1]
	at com.google.common.eventbus.DefaultGuavaEventBus.dispatch(DefaultGuavaEventBus.java:41) [com.google.guava:16.0.1]
	at com.google.common.eventbus.ReentrantGuavaEventBus.dispatchQueuedEvents(ReentrantGuavaEventBus.java:56) [com.google.guava:16.0.1]
	at com.google.common.eventbus.EventBus.post(EventBus.java:275) [com.google.guava:16.0.1]
	at org.sonatype.sisu.goodies.eventbus.internal.DefaultEventBus.post(DefaultEventBus.java:73) [com.google.guava:16.0.1]
	at org.sonatype.security.DefaultSecuritySystem.deleteUser(DefaultSecuritySystem.java:418) [org.sonatype.nexus.core:3.0.0.SNAPSHOT]
	at org.sonatype.security.SecuritySystem$deleteUser.call(Unknown Source) [3.0.0-SNAPSHOT:3.0.0-SNAPSHOT]
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:45) [groovy-all:2.1.5]
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108) [groovy-all:2.1.5]
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:120) [groovy-all:2.1.5]
	at org.sonatype.nexus.coreui.UserComponent.delete_(UserComponent.groovy:292) [org.sonatype.nexus.plugins.nexus-coreui-plugin:3.0.0.SNAPSHOT]