Modules/LDAPObject.c (l_ldap_passwd): Accept None for user, oldpw, newpw
(partially fixes #291230, SF#1440151).

--- python-ldap-2.2.0~/Modules/LDAPObject.c
+++ python-ldap-2.2.0/Modules/LDAPObject.c
@@ -2,7 +2,7 @@
 
 /* 
  * LDAPObject - wrapper around an LDAP* context
- * $Id: LDAPObject.c,v 1.74 2006/04/05 22:40:14 stroeder Exp $
+ * $Id: LDAPObject.c,v 1.75 2006/04/18 11:17:30 stroeder Exp $
  */
 
 #include "Python.h"
@@ -1179,7 +1179,7 @@
     int msgid;
     int ldaperror;
 
-    if (!PyArg_ParseTuple( args, "s#s#s#|OO", &user.bv_val, &user_len, &oldpw.bv_val, &oldpw_len, &newpw.bv_val, &newpw_len, &serverctrls, &clientctrls ))
+    if (!PyArg_ParseTuple( args, "z#z#z#|OO", &user.bv_val, &user_len, &oldpw.bv_val, &oldpw_len, &newpw.bv_val, &newpw_len, &serverctrls, &clientctrls ))
     	return NULL;
 
     user.bv_len = (ber_len_t) user_len;
@@ -1201,7 +1201,13 @@
     }
 
     LDAP_BEGIN_ALLOW_THREADS( self );
-    ldaperror = ldap_passwd( self->ldap, &user, &oldpw, &newpw, server_ldcs, client_ldcs, &msgid );
+    ldaperror = ldap_passwd( self->ldap,
+            user.bv_val != NULL ? &user : NULL,
+            oldpw.bv_val != NULL ? &oldpw : NULL,
+            newpw.bv_val != NULL ? &newpw : NULL,
+            server_ldcs,
+            client_ldcs,
+            &msgid );
     LDAP_END_ALLOW_THREADS( self );
     
     LDAPControl_List_DEL( server_ldcs );