You'd need to make sure ANR is enabled in the parameter that you want to use for the search in your LDAP.
Then, in the .xml file make sure ANR is enabled, and add that LDAP attribute to the PredictiveSearchFilter.
http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/jabber/11_8/cjab_b_parameters-reference-guide-jabber-118/cjab_b_parameters-reference-guide-jabber-118_chapter_01010.html
HTH
java
if this helps, please rate