--- mozilla/configure.in.orig	2010-06-23 19:43:07.000000000 +0200
+++ mozilla/configure.in	2010-07-06 11:14:54.350499449 +0200
@@ -5032,6 +5032,13 @@
     MOZ_LDAP_XPCOM=,
     MOZ_LDAP_XPCOM=1)
 
+dnl system LDAP Support
+dnl ========================================================
+MOZ_ARG_WITH_STRING(system-ldap,
+[  --with-system-ldap[=PFX]
+                          Use system mozldap [installed at prefix PFX]],
+    MOZ_LDAP_DIR=$withval)
+
 dnl ========================================================
 dnl = Trademarked Branding 
 dnl ========================================================
@@ -7612,7 +7619,7 @@
 
 # if we're building the LDAP XPCOM component, we need to build 
 # the c-sdk first.  
-if test -n "$COMPILE_ENVIRONMENT" -a -n "$MOZ_LDAP_XPCOM"; then
+if test -n "$COMPILE_ENVIRONMENT" -a -n "$MOZ_LDAP_XPCOM" -a -z "$MOZ_LDAP_DIR"; then
     # these subdirs may not yet have been created in the build tree.
     # don't use the "-p" switch to mkdir, since not all platforms have it
     if test ! -d "directory/c-sdk/ldap"; then