[gtkmm-documentation] Add AC_PROG_CXX to avoid circular dependency aclocal error.

[Murray Cumming <murrayc src gnome org>]

commit 4768053f8fd96908892cf8314b13be8a6bed8190
Author: Murray Cumming <murrayc murrayc com>
Date:   Thu Jun 25 11:43:53 2009 +0200

    Add AC_PROG_CXX to avoid circular dependency aclocal error.
    Bug #586700.

 ChangeLog    |    5 +++++
 configure.in |    1 +
 2 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index b76adef..5810ec9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-06-25   Stas Sergeev  <stsp aknet ru>
+
+	* configure.in: Add AC_PROG_CXX to avoid circular dependency aclocal error.
+	Bug #586700.
+
 2009-06-02  Murray Cumming  <murrayc murrayc com>
 
 	* docs/tutorial/C/gtkmm-tut.xml: Clipboard: Paste: Discovering Available 
diff --git a/configure.in b/configure.in
index c58aa5a..2eaba99 100644
--- a/configure.in
+++ b/configure.in
@@ -73,6 +73,7 @@ AL_ACLOCAL_INCLUDE(scripts)
 #########################################################################
 AC_PROG_CC
 AC_PROG_CPP
+AC_PROG_CXX
 AC_PROG_MAKE_SET
 AC_CANONICAL_BUILD
 AC_CANONICAL_HOST