[SM-PLUGINS] ldappass - undefined function

[<da...@sm...>]

Hello, I have installed the change_ldappass 1.4 plugin in my Squirrelmail
1.2.9 with RedHat 7.3 and when I run the plugin I get the following error
message

--------------------8<-------------------------------
Fatal error: Call to undefined function: ldap_connect() in
/usr/share/squirrelmail/plugins/change_ldappass/options.php on line 122
--------------------------------------------------------


I can't find the reasons.
Please, I need your help!

Thanks, Danilo.