bash extensions

[Roman Kurakin]

For OS's that do not use bash as default shell there is some problems with
configure cause of usage of bash extensions.
--- aclocal.m4.orig     Sun Jan 29 16:16:42 2006
+++ aclocal.m4  Sun Jan 29 16:18:49 2006
@@ -424,7 +424,7 @@
 EOF
        FLEXLEXER_PATH=`$CXX -E conftest.cc | \
          sed 's!# 1 "\(.*\)FlexLexer.h"address@hidden@\1@@!g' | grep '@@' | \
-         sed 'address@hidden@\(.*\)@@.*$!\1!g' ` >& /dev/null
+         sed 'address@hidden@\(.*\)@@.*$!\1!g' ` 1>/dev/null 2>/dev/null
        rm conftest.cc
        AC_SUBST(FLEXLEXER_PATH)
         AC_MSG_RESULT($FLEXLEXER_PATH)
@@ -1208,11 +1208,11 @@
     AC_CYGWIN
     AC_MINGW32
                                                                                
-    if test "$CYGWIN" == "yes"; then
+    if test "$CYGWIN" = "yes"; then
        LN_S='cp -r' # Cygwin symbolic links do not work for native apps.
        program_suffix=.exe
        INSTALL="\$(SHELL) \$(stepdir)/../bin/install-dot-exe.sh -c"
-    elif test "$MINGW32" == "yes"; then
+    elif test "$MINGW32" = "yes"; then
        LN='cp -r'
        LN_S='cp -r'
        program_suffix=.exe
@@ -1230,7 +1230,7 @@
     AC_SUBST(program_suffix)
                                                                                
     AC_MSG_CHECKING([for some flavor of Windows])
-    if test "$CYGWIN$MINGW32" == "nono"; then
+    if test "$CYGWIN$MINGW32" = "nono"; then
         PLATFORM_WINDOWS=no
     else
         PLATFORM_WINDOWS=yes