diff --git a/m4/ax_is_release.m4 b/m4/ax_is_release.m4
index 9ec67469..c728b1e7 100644
--- a/m4/ax_is_release.m4
+++ b/m4/ax_is_release.m4
@@ -39,7 +39,7 @@
 #   permitted in any medium without royalty provided the copyright notice
 #   and this notice are preserved.
 
-#serial 3
+#serial 4
 
 AC_DEFUN([AX_IS_RELEASE],[
     AC_BEFORE([AC_INIT],[$0])
@@ -47,7 +47,7 @@ AC_DEFUN([AX_IS_RELEASE],[
     m4_case([$1],
       [git-directory],[
         # $is_release = (.git directory does not exist)
-        AS_IF([test -d .git],[ax_is_release=no],[ax_is_release=yes])
+        AS_IF([test -d ${top_srcdir}/.git],[ax_is_release=no],[ax_is_release=yes])
       ],
       [minor-version],[
         # $is_release = ($minor_version is even)