Symptoms

• Directory sync fails with errors such as this:

  2013-03-28 14:44:10,444 ERROR [scheduler_Worker-7] [atlassian.crowd.directory.DbCachingDirectoryPoller] pollChanges Error occurred while refreshing the cache for directory [ 851969 ].
  java.lang.IllegalArgumentException: can't parse argument number 2z
  

• With Detailed SQL Logging turned on, you realize that there are groups synchronized with curly braces enclosing the string highlighted by the error:

  2013-03-28 14:44:10,430 TRACE [scheduler_Worker-7] [sf.hibernate.type.StringType] nullSafeGet returning 'userGroup {2z}' as column: group_name0_
  2013-03-28 14:44:10,430 TRACE [scheduler_Worker-7] [sf.hibernate.type.StringType] nullSafeGet returning 'usergroup {2z}' as column: lower_gr3_0_
  

  2013-03-28 14:44:10,434 TRACE [scheduler_Worker-7] [sf.hibernate.type.StringType] nullSafeSet binding 'usergroup {2z}' to parameter: 1
  

Cause

Confluence parses the curly braces as a numerical argument.

Observation

• If the groupname instead, is this: usergroup {2}

  , the error will not be thrown

• Only happens in Confluence 5.1.
• Confluence 5.0 and below are not affected

Workaround

Change the Group/User Object Filter to something like this (to filter out groups/users containing the curly braces):

(&(objectCategory=Group)(!(cn=*{*}*)))

(&(objectCategory=Person)(!(cn=*{*}*)))

The example above applies for Active Directory with the username attribute and groupname attribute set to cn