LDAP connection open method fails with annonymous (empty) DN

java.lang.StringIndexOutOfBoundsException: String index out of range: 4
at java.lang.StringBuffer.charAt(StringBuffer.java:162)
at com.novell.ldap.LDAPDN.escapeRDN(Unknown Source)
at com.xpn.xwiki.plugin.ldap.XWikiLDAPConnection.escapeLDAPDNValue(XWikiLDAPConnection.java:381)
at com.xpn.xwiki.plugin.ldap.XWikiLDAPConfig.getLDAPBindDN(XWikiLDAPConfig.java:400)
at com.xpn.xwiki.plugin.ldap.XWikiLDAPConnection.open(XWikiLDAPConnection.java:91)
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.codehaus.groovy.runtime.callsite.PojoMetaMethodSite$PojoCachedMethodSiteNoUnwrapNoCoerce.invoke(PojoMetaMethodSite.java:229)
at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:52)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:40)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:132)
at Script1.run(Script1.groovy:84)
at groovy.lang.GroovyShell.evaluate(GroovyShell.java:576)
at groovy.lang.GroovyShell.evaluate(GroovyShell.java:614)
at groovy.lang.GroovyShell.evaluate(GroovyShell.java:585)
at com.xpn.xwiki.plugin.scheduler.GroovyJob.executeJob(GroovyJob.java:85)
at com.xpn.xwiki.plugin.scheduler.AbstractJob.execute(AbstractJob.java:75)
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:525)