Index: contrib/mod_ldap.c
===================================================================
RCS file: /cvsroot/proftp/proftpd/contrib/mod_ldap.c,v
retrieving revision 1.94
diff -u -r1.94 mod_ldap.c
--- contrib/mod_ldap.c	18 Nov 2011 17:34:02 -0000	1.94
+++ contrib/mod_ldap.c	7 Dec 2011 22:38:07 -0000
@@ -1978,15 +1979,17 @@
     ldap_do_users = 1;
     ldap_user_basedn = pstrdup(session.pool, c->argv[0]);
 
-    if (c->argv[1]) {
+    if (c->argc > 1) {
       ldap_user_name_filter = pstrdup(session.pool, c->argv[1]);
+
     } else {
       ldap_user_name_filter = pstrcat(session.pool,
         "(&(", ldap_attr_uid, "=%v)(objectclass=posixAccount))", NULL);
     }
 
-    if (c->argv[2]) {
+    if (c->argc > 2) {
       ldap_user_uid_filter = pstrdup(session.pool, c->argv[2]);
+
     } else {
       ldap_user_uid_filter = pstrcat(session.pool,
         "(&(", ldap_attr_uidnumber, "=%v)(objectclass=posixAccount))", NULL);