diff --git a/ChangeLog b/ChangeLog
index 912f793cf..005e87541 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2011-11-08  Richard Henderson  <rth@redhat.com>
+
+	* configure.ac: Test for libitm directory present first.
+
+	* configure.ac: Adjust srcdir for running libitm/configure.tgt.
+
+	* configure.ac: Test libitm/configure.tgt to disable libitm.
+	* configure: Rebuild.
+
 2011-11-02  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* Makefile.tpl (EXTRA_GCC_FLAGS): Remove LIBGCC2_CFLAGS,
diff --git a/configure b/configure
index c2a512754..40922de5d 100755
--- a/configure
+++ b/configure
@@ -2681,6 +2681,7 @@ target_libraries="target-libgcc \
 		target-libgloss \
 		target-newlib \
 		target-libgomp \
+		target-libitm \
 		target-libstdc++-v3 \
 		target-libmudflap \
 		target-libssp \
@@ -3056,6 +3057,25 @@ if test x$enable_libgomp = x ; then
     esac
 fi
 
+# Disable libitm on unsupported systems.
+if test -d ${srcdir}/libitm; then
+    if test x$enable_libitm = x; then
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for libitm support" >&5
+$as_echo_n "checking for libitm support... " >&6; }
+	if (srcdir=${srcdir}/libitm; \
+		. ${srcdir}/configure.tgt; \
+		test -n "$UNSUPPORTED")
+	then
+	    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+	    noconfigdirs="$noconfigdirs target-libitm"
+	else
+	    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+	fi
+    fi
+fi
+
 # Disable libssp for some systems.
 case "${target}" in
   avr-*-*)
diff --git a/configure.ac b/configure.ac
index 2745bd7d8..ea697d393 100644
--- a/configure.ac
+++ b/configure.ac
@@ -154,6 +154,7 @@ target_libraries="target-libgcc \
 		target-libgloss \
 		target-newlib \
 		target-libgomp \
+		target-libitm \
 		target-libstdc++-v3 \
 		target-libmudflap \
 		target-libssp \
@@ -492,6 +493,22 @@ if test x$enable_libgomp = x ; then
     esac
 fi
 
+# Disable libitm on unsupported systems.
+if test -d ${srcdir}/libitm; then
+    if test x$enable_libitm = x; then
+	AC_MSG_CHECKING([for libitm support])
+	if (srcdir=${srcdir}/libitm; \
+		. ${srcdir}/configure.tgt; \
+		test -n "$UNSUPPORTED")
+	then
+	    AC_MSG_RESULT([no])
+	    noconfigdirs="$noconfigdirs target-libitm"
+	else
+	    AC_MSG_RESULT([yes])
+	fi
+    fi
+fi
+
 # Disable libssp for some systems.
 case "${target}" in
   avr-*-*)