# yum list installed *ldap* 
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Installed Packages
nss_ldap.i386                                                      253-37.el5_6.1                                          installed
nss_ldap.x86_64                                                    253-37.el5_6.1                                          installed
openldap.i386                                                      2.3.43-25.el5                                           installed
openldap.x86_64                                                    2.3.43-25.el5                                           installed
openldap-clients.x86_64                                            2.3.43-25.el5                                           installed
openldap-servers.x86_64                                            2.3.43-25.el5                                           installed
openldap-servers-sql.x86_64                                        2.3.43-25.el5                                           installed
php-ldap.x86_64                                                    5.1.6-27.el5_7.4                                        installed..