`test x == x` gives a syntax error with dash (standard in Debian).
The modified patch reflects the current upstream:
http://git.savannah.gnu.org/cgit/quilt.git/commit/?id=
38df0b210c3df67f3e784af92232ae1946b98ecd
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@26804
3c298f89-4303-0410-b956-
a3cf2f4a3e73
--- a/configure.ac
+++ b/configure.ac
-@@ -274,7 +274,7 @@ fi
+@@ -274,7 +274,11 @@ fi
AC_MSG_CHECKING([the version of $PATCH])
if $PATCH --version 2> /dev/null | grep GNU >/dev/null; then
set -- `$PATCH --version 2> /dev/null`
- patch_version=$2
-+ test $2 == "patch" && patch_version=$3 || patch_version=$2
++ if test x$1 = xGNU ; then
++ patch_version=$3
++ else
++ patch_version=$2
++ fi
AC_MSG_RESULT($patch_version)
saved_IFS=$IFS; IFS='.'
set -- $patch_version