This came in via the forums:

http://forums.atlassian.com/post!reply.jspa?messageID=257256340

I'm using Crowd 1.1.2 with Sun Directory Server EE 6.2 (this was previously SunONE). The initial import of users from JIRA worked fine. However, when I try to create a new user in JIRA, I get this error:

com.opensymphony.user.ImmutableException: No provider successfully created entity rivertest
at com.opensymphony.user.UserManager.createEntity(UserManager.java:379)

Crowd logs this:

06:17:09,935 ERROR org.codehaus.xfire.handler.DefaultFaultHandler: Fault occurred!
java.lang.NullPointerException
at com.atlassian.crowd.integration.directory.connector.SunONE.getPassword(SunONE.java:41)
at com.atlassian.crowd.integration.directory.connector.SunONE.addPrincipal(SunONE.java:62)

Looking at the source code it appears that the credentials for the user are null.

ie a null List of 'null' credentials are being passed to our SunOne code, which is a little weird.