Update m4 for curl

diff --git a/m4/acx_libcurl.m4 b/m4/acx_libcurl.m4
index d4de7c6..8cada05 100644
--- a/m4/acx_libcurl.m4
+++ b/m4/acx_libcurl.m4
@@ -1,27 +1,3 @@
-# $Id$
-
-# COPYRIGHT AND PERMISSION NOTICE
-#
-# Copyright (c) 1996 - 2010, Daniel Stenberg, <daniel@haxx.se>.
-#
-# All rights reserved.
-#
-# Permission to use, copy, modify, and distribute this software for any purpose
-# with or without fee is hereby granted, provided that the above copyright
-# notice and this permission notice appear in all copies.
-#
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN
-# NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
-# DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
-# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
-# OR OTHER DEALINGS IN THE SOFTWARE.
-#
-# Except as contained in this notice, the name of a copyright holder shall not
-# be used in advertising or otherwise to promote the sale, use or other dealings
-# in this Software without prior written authorization of the copyright holder.
-
 # LIBCURL_CHECK_CONFIG ([DEFAULT-ACTION], [MINIMUM-VERSION],
 #                       [ACTION-IF-YES], [ACTION-IF-NO])
 # ----------------------------------------------------------
@@ -85,7 +61,7 @@ AC_DEFUN([LIBCURL_CHECK_CONFIG],
  AH_TEMPLATE([LIBCURL_PROTOCOL_SMTP],[Defined if libcurl supports SMTP])

  AC_ARG_WITH(libcurl,
-     AC_HELP_STRING([--with-libcurl=DIR],[look for the curl library in DIR]),
+     AC_HELP_STRING([--with-libcurl=PREFIX],[look for the curl library in PREFIX/lib and headers in PREFIX/include]),
     [_libcurl_with=$withval],[_libcurl_with=ifelse([$1],,[yes],[$1])])

  if test "$_libcurl_with" != "no" ; then
@@ -99,10 +75,10 @@ AC_DEFUN([LIBCURL_CHECK_CONFIG],
     if test -d "$_libcurl_with" ; then
        LIBCURL_CPPFLAGS="-I$withval/include"
        _libcurl_ldflags="-L$withval/lib"
-        AC_PATH_PROG([_libcurl_config],[curl-config],["$withval/bin"],
+        AC_PATH_PROG([_libcurl_config],[curl-config],[],
                     ["$withval/bin"])
     else
-        AC_PATH_PROG([_libcurl_config],[curl-config])
+        AC_PATH_PROG([_libcurl_config],[curl-config],[],[$PATH])
     fi

     if test x$_libcurl_config != "x" ; then
@@ -170,7 +146,7 @@ AC_DEFUN([LIBCURL_CHECK_CONFIG],
           _libcurl_save_libs=$LIBS
           LIBS="$LIBCURL $LIBS"

-           AC_LINK_IFELSE(AC_LANG_PROGRAM([#include <curl/curl.h>],[
+           AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <curl/curl.h>],[
 /* Try and use a few common options to force a failure if we are
   missing symbols or can't link. */
 int x;
@@ -181,7 +157,8 @@ x=CURLOPT_FILE;
 x=CURLOPT_ERRORBUFFER;
 x=CURLOPT_STDERR;
 x=CURLOPT_VERBOSE;
-]),libcurl_cv_lib_curl_usable=yes,libcurl_cv_lib_curl_usable=no)
+if (x) ;
+])],libcurl_cv_lib_curl_usable=yes,libcurl_cv_lib_curl_usable=no)

           CPPFLAGS=$_libcurl_save_cppflags
           LIBS=$_libcurl_save_libs

diff --git a/m4/acx_libcurl.m4 b/m4/acx_libcurl.m4
index 8cada05..d7d5a52 100644
--- a/m4/acx_libcurl.m4
+++ b/m4/acx_libcurl.m4
@@ -146,7 +146,7 @@ AC_DEFUN([LIBCURL_CHECK_CONFIG],
           _libcurl_save_libs=$LIBS
           LIBS="$LIBCURL $LIBS"

-           AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <curl/curl.h>],[
+           AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <curl/curl.h>]],[[
 /* Try and use a few common options to force a failure if we are
   missing symbols or can't link. */
 int x;
@@ -158,7 +158,7 @@ x=CURLOPT_ERRORBUFFER;
 x=CURLOPT_STDERR;
 x=CURLOPT_VERBOSE;
 if (x) ;
-])],libcurl_cv_lib_curl_usable=yes,libcurl_cv_lib_curl_usable=no)
+]])],libcurl_cv_lib_curl_usable=yes,libcurl_cv_lib_curl_usable=no)

           CPPFLAGS=$_libcurl_save_cppflags
           LIBS=$_libcurl_save_libs