Unable to Add Users into a Group Due to Lack of Permission

2012-09-20 07:03:09,718 INFO [read-only-transaction:thread-1] [atlassian.confluence.user.DefaultUserAccessor] getUserNamesWithConfluenceAccess Could not find group configured with USE permission: null
2012-09-20 07:05:29,343 ERROR [http-8080-4] [bucket.user.DefaultUserAccessor] addMembership Failed to add '<username>' as a member of '<group-name>'
 -- referer: http://<confluence-url>/admin/users/docreateuser.action | url: /admin/users/docreateuser.action | userName: admin | action: docreateuser
com.atlassian.user.EntityException: com.atlassian.crowd.exception.OperationNotPermittedException: com.atlassian.crowd.exception.ApplicationPermissionException: Cannot update group '<group-name>' because directory '<user-directory-name>' does not allow updates.
    at com.atlassian.crowd.embedded.atlassianuser.EmbeddedCrowdGroupManager.addMembership(EmbeddedCrowdGroupManager.java:169)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
....
Caused by: com.atlassian.crowd.exception.OperationNotPermittedException: com.atlassian.crowd.exception.ApplicationPermissionException: Cannot update group '<group-name>' because directory '<user-directory-name>' does not allow updates.
    at com.atlassian.crowd.embedded.core.CrowdServiceImpl.addUserToGroup(CrowdServiceImpl.java:679)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:307)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
    at $Proxy24.addUserToGroup(Unknown Source)
    at com.atlassian.crowd.embedded.atlassianuser.EmbeddedCrowdGroupManager.addMembership(EmbeddedCrowdGroupManager.java:165)
    ... 240 more
Caused by: com.atlassian.crowd.exception.ApplicationPermissionException: Cannot update group '<group-name>' because directory '<user-directory-name>' does not allow updates.
    at com.atlassian.crowd.manager.application.ApplicationServiceGeneric.addUserToGroup(ApplicationServiceGeneric.java:1057)
    at com.atlassian.crowd.embedded.core.CrowdServiceImpl.addUserToGroup(CrowdServiceImpl.java:675)
    ... 252 more