diff --git a/config/autoconf.mk.in b/config/autoconf.mk.in

--- a/config/autoconf.mk.in

+++ b/config/autoconf.mk.in

@@ -421,16 +421,17 @@ NSPR_CONFIG	= @NSPR_CONFIG@

 NSPR_CFLAGS	= @NSPR_CFLAGS@

 NSPR_LIBS	= @NSPR_LIBS@

 NSS_CONFIG	= @NSS_CONFIG@

 NSS_CFLAGS	= @NSS_CFLAGS@

 NSS_LIBS	= @NSS_LIBS@

 NSS_DEP_LIBS	= @NSS_DEP_LIBS@

+MOZ_NATIVE_MOZLDAP = @SYSTEM_MOZLDAP@

 LDAP_CFLAGS	= @LDAP_CFLAGS@

 LDAP_LIBS	= @LDAP_LIBS@

 XPCOM_GLUE_LDOPTS = @XPCOM_GLUE_LDOPTS@

 XPCOM_STANDALONE_GLUE_LDOPTS = @XPCOM_STANDALONE_GLUE_LDOPTS@

 MOZ_XPCOM_OBSOLETE_LIBS = @MOZ_XPCOM_OBSOLETE_LIBS@

 USE_DEPENDENT_LIBS = @USE_DEPENDENT_LIBS@

diff --git a/configure.in b/configure.in

--- a/configure.in

+++ b/configure.in

@@ -4936,16 +4936,34 @@ dnl ====================================

 dnl = LDAP

 dnl =========================================================

 MOZ_ARG_DISABLE_BOOL(ldap,

 [  --disable-ldap          Disable LDAP support],

     MOZ_LDAP_XPCOM=,

     MOZ_LDAP_XPCOM=1)

 dnl ========================================================

+dnl = If mozldap was not detected in the system, 

+dnl = use the one in the source tree (mozilla/directory/c-sdk)

+dnl ========================================================

+

+if test -n "$MOZ_LDAP_XPCOM"; then

+  MOZ_ARG_ENABLE_BOOL(system-mozldap,

+  [  --enable-system-mozldap  

+                          Use system installed mozldap (located with pkgconfig)],

+      SYSTEM_MOZLDAP=1 )

+

+  if test -n "$SYSTEM_MOZLDAP"; then

+      PKG_CHECK_MODULES(MOZLDAP, mozldap >= 6.0.6,

+        SYSTEM_MOZLDAP=1, SYSTEM_MOZLDAP=)

+  fi

+fi

+AC_SUBST(SYSTEM_MOZLDAP)

+

+dnl ========================================================

 dnl = Trademarked Branding 

 dnl ========================================================

 MOZ_ARG_ENABLE_BOOL(official-branding,

 [  --enable-official-branding Enable Official mozilla.org Branding

                           Do not distribute builds with

                           --enable-official-branding unless you have

                           permission to use trademarks per

                           http://www.mozilla.org/foundation/trademarks/ .],

@@ -7043,17 +7061,22 @@ if test "$MOZ_LDAP_XPCOM"; then

         if test -n "$GNU_CC"; then

             LDAP_LIBS='-L$(DIST)/lib -lnsldap32v60 -lnsldappr32v60 -lnsldif32v60'

         else

             LDAP_LIBS='$(DIST)/lib/$(LIB_PREFIX)nsldap32v60.${IMPORT_LIB_SUFFIX} $(DIST)/lib/$(LIB_PREFIX)nsldappr32v60.${IMPORT_LIB_SUFFIX} $(DIST)/lib/$(LIB_PREFIX)nsldif32v60.${IMPORT_LIB_SUFFIX}'

         fi

     elif test "$OS_ARCH" = "OS2"; then

             LDAP_LIBS='$(DIST)/lib/$(LIB_PREFIX)ldap60.${IMPORT_LIB_SUFFIX} $(DIST)/lib/$(LIB_PREFIX)prldap60.${IMPORT_LIB_SUFFIX} $(DIST)/lib/$(LIB_PREFIX)ldif60.${IMPORT_LIB_SUFFIX}'

     else

-        LDAP_LIBS='-L${DIST}/bin -L${DIST}/lib -lldap60 -lprldap60 -lldif60'

+        if test "$SYSTEM_MOZLDAP"; then

+            LDAP_LIBS="$MOZLDAP_LIBS"

+            LDAP_CFLAGS="$MOZLDAP_CFLAGS"

+        else

+            LDAP_LIBS='-L${DIST}/bin -L${DIST}/lib -lldap60 -lprldap60 -lldif60'

+        fi

     fi

 fi

 dnl ========================================================

 dnl =

 dnl = Maintainer debug option (no --enable equivalent)

 dnl =

 dnl ========================================================

@@ -7603,17 +7626,17 @@ fi

 AC_OUTPUT_SUBDIRS(mozilla)

 ac_configure_args="$_SUBDIR_CONFIG_ARGS"

 MOZ_BUILD_APP="$MOZ_BUILD_APP_CACHED"

 if test "$COMPILE_ENVIRONMENT"; then

 # if we're building the LDAP XPCOM component, we need to build 

 # the c-sdk first.  

 #

-if test "$MOZ_LDAP_XPCOM"; then

+if test "$MOZ_LDAP_XPCOM" -a -z "$SYSTEM_MOZLDAP" ; 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"; then

         mkdir "directory"

     fi

     if test ! -d "directory/c-sdk"; then

diff --git a/mail/build.mk b/mail/build.mk

--- a/mail/build.mk

+++ b/mail/build.mk

@@ -47,17 +47,19 @@ ifdef MOZ_EXTENSIONS

 tier_app_dirs += extensions

 endif

 else # toplevel Makefile

 TIERS += app

 ifdef MOZ_LDAP_XPCOM

+ifndef MOZ_NATIVE_MOZLDAP

 tier_app_staticdirs += directory/c-sdk

+endif

 tier_app_dirs += directory/xpcom

 endif

 ifdef MOZ_COMPOSER

 tier_app_dirs += editor/ui

 endif

 ifdef MOZ_BRANDING_DIRECTORY

diff --git a/suite/build.mk b/suite/build.mk

--- a/suite/build.mk

+++ b/suite/build.mk

@@ -47,17 +47,19 @@ ifdef MOZ_EXTENSIONS

 tier_app_dirs += extensions

 endif

 else # toplevel Makefile

 TIERS += app

 ifdef MOZ_LDAP_XPCOM

+ifndef MOZ_NATIVE_MOZLDAP

 tier_app_staticdirs += directory/c-sdk

+endif

 tier_app_dirs += directory/xpcom

 endif

 ifdef MOZ_COMPOSER

 tier_app_dirs += editor/ui

 endif

 ifdef MOZ_BRANDING_DIRECTORY