User Profile for LDAP Users Hangs Indefinitely: Server CPU Stays at 100% and Memory Increases Until the Server Grinds to a Halt

Problem Scenario:
1) Configure xwiki.cfg to use LDAP service on MS Active Directory
2) Start XWiki
3) User logs in with LDAP account for first time
4) XWiki successfully creates user's account from LDAP information
5) User logs out
6) Admin user modifies and saves user's profile: information, avatar
7) User logs in
8) User tries to access his profile page
9) Server response times out in user's browser
10) Server stats show javaw.exe process is running at 100% CPU and rapidly consuming more and more memory
11) Server admin must terminate javaw.exe process tree and restart XWiki.

P.S. Jetty log shows the following error messages if you don't kill the process:
INFO | jvm 1 | 2009/07/21 15:57:33 | Exception in thread "Timer-1" Exception in thread "HSQLDB Timer @1fcbac1" java.lang.OutOfMemoryError: Java heap space
INFO | jvm 1 | 2009/07/21 15:57:33 | java.lang.OutOfMemoryError: Java heap space
INFO | jvm 1 | 2009/07/21 15:57:34 | at java.lang.AbstractStringBuilder.<init>(Unknown Source)
INFO | jvm 1 | 2009/07/21 15:57:34 | at java.lang.StringBuffer.<init>(Unknown Source)
INFO | jvm 1 | 2009/07/21 15:57:34 | at org.hsqldb.persist.LockFile$HeartbeatRunner.run(Unknown Source)
INFO | jvm 1 | 2009/07/21 15:57:34 | at org.hsqldb.lib.HsqlTimer$TaskRunner.run(Unknown Source)
INFO | jvm 1 | 2009/07/21 15:57:34 | at java.lang.Thread.run(Unknown Source)

This scenario works fine if the user is created locally in XWiki by the Admin user. It seems like something breaks as soon as the scenario is used by a user created from LDAP (MS Active Directory).

This is currently a show-stopper for our organization's adoption of XWiki.