diff --git a/configure.ac b/configure.ac
index 892b4c9..ca45b0a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -8,9 +8,10 @@ AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_HEADER(config.h)
 
 # GIT revison
-define([git_revision], esyscmd([sh -c "git describe"]))
-GIT_REVISION=git_revision
-AC_DEFINE_UNQUOTED([GIT_REVISION], ["$GIT_REVISION"], [GIT revision])
+GIT_REVISION=`which git > /dev/null && git describe`
+if test x"$GIT_REVISION" != x""; then
+    AC_DEFINE_UNQUOTED([GIT_REVISION], ["$GIT_REVISION"], [GIT revision])
+fi
 
 AM_INIT_AUTOMAKE
 m4_ifdef([AM_PROG_AR], [AM_PROG_AR])