--- a/config.m4
+++ b/config.m4
@@ -28,7 +28,7 @@ if test "$PHP_COUCHBASE" != "no"; then

   dnl fallback on standard directory
   else
-    for i in /usr/local /usr; do
+    for i in @libcouchbase@; do
       if test -r $i/include/libcouchbase/couchbase.h; then
         LIBCOUCHBASE_DIR=$i
         AC_MSG_RESULT(found in $i)