Patch 659834 by Magnus Lie Hetland:

Check for readline 2.2 features.  This should make it possible to
compile readline.c again with GNU readline versions 2.0 or 2.1; this
ability was removed in readline.c rev. 2.49.  Apparently the older
versions are still in widespread deployment on older Solaris
installations.  With an older readline, completion behavior is subtly
different (a space is always added).
diff --git a/Modules/readline.c b/Modules/readline.c
index 462d52f..a4bfc62 100644
--- a/Modules/readline.c
+++ b/Modules/readline.c
@@ -574,7 +574,9 @@
 	rl_completer_word_break_characters =
 		strdup(" \t\n`~!@#$%^&*()-=+[{]}\\|;:'\",<>/?");
 		/* All nonalphanums except '.' */
+#ifdef HAVE_RL_COMPLETION_APPEND_CHARACTER
 	rl_completion_append_character ='\0';
+#endif
 
 	begidx = PyInt_FromLong(0L);
 	endidx = PyInt_FromLong(0L);
@@ -626,7 +628,9 @@
         if (sys_stdin != rl_instream || sys_stdout != rl_outstream) {
                 rl_instream = sys_stdin;
                 rl_outstream = sys_stdout;
+#ifdef HAVE_RL_COMPLETION_APPEND_CHARACTER
                 rl_prep_terminal (1);
+#endif
         }
         
 	p = readline(prompt);
diff --git a/configure b/configure
index 207eddf..5495840 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.in Revision: 1.378 .
+# From configure.in Revision: 1.380 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.53 for python 2.3.
 #
@@ -908,7 +908,7 @@
 # Don't blindly perform a `cd "$ac_dir"/$ac_foo && pwd` since $ac_foo can be
 # absolute.
 ac_abs_builddir=`cd "$ac_dir" && cd $ac_builddir && pwd`
-ac_abs_top_builddir=`cd "$ac_dir" && cd ${ac_top_builddir}. && pwd`
+ac_abs_top_builddir=`cd "$ac_dir" && cd $ac_top_builddir && pwd`
 ac_abs_srcdir=`cd "$ac_dir" && cd $ac_srcdir && pwd`
 ac_abs_top_srcdir=`cd "$ac_dir" && cd $ac_top_srcdir && pwd`
 
@@ -16228,6 +16228,56 @@
 
 fi
 
+# check for readline 2.2
+cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <readline/readline.h>
+_ACEOF
+if { (eval echo "$as_me:$LINENO: \"$ac_cpp conftest.$ac_ext\"") >&5
+  (eval $ac_cpp conftest.$ac_ext) 2>conftest.er1
+  ac_status=$?
+  egrep -v '^ *\+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } >/dev/null; then
+  if test -s conftest.err; then
+    ac_cpp_err=$ac_c_preproc_warn_flag
+  else
+    ac_cpp_err=
+  fi
+else
+  ac_cpp_err=yes
+fi
+if test -z "$ac_cpp_err"; then
+  have_readline=yes
+else
+  echo "$as_me: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  have_readline=no
+fi
+rm -f conftest.err conftest.$ac_ext
+if test $have_readline = yes
+then
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <readline/readline.h>
+
+_ACEOF
+if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
+  egrep "extern int rl_completion_append_character;" >/dev/null 2>&1; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_RL_COMPLETION_APPEND_CHARACTER 1
+_ACEOF
+
+fi
+rm -f conftest*
+
+fi
+
 # check for readline 4.0
 echo "$as_me:$LINENO: checking for rl_pre_input_hook in -lreadline" >&5
 echo $ECHO_N "checking for rl_pre_input_hook in -lreadline... $ECHO_C" >&6
@@ -17418,7 +17468,7 @@
 # Don't blindly perform a `cd "$ac_dir"/$ac_foo && pwd` since $ac_foo can be
 # absolute.
 ac_abs_builddir=`cd "$ac_dir" && cd $ac_builddir && pwd`
-ac_abs_top_builddir=`cd "$ac_dir" && cd ${ac_top_builddir}. && pwd`
+ac_abs_top_builddir=`cd "$ac_dir" && cd $ac_top_builddir && pwd`
 ac_abs_srcdir=`cd "$ac_dir" && cd $ac_srcdir && pwd`
 ac_abs_top_srcdir=`cd "$ac_dir" && cd $ac_top_srcdir && pwd`
 
diff --git a/configure.in b/configure.in
index b4bbdb6..4869dd1 100644
--- a/configure.in
+++ b/configure.in
@@ -2381,6 +2381,17 @@
   [Define this if you have flockfile(), getc_unlocked(), and funlockfile()])
 fi
 
+# check for readline 2.2
+AC_TRY_CPP([#include <readline/readline.h>],
+have_readline=yes, have_readline=no)
+if test $have_readline = yes
+then
+  AC_EGREP_HEADER([extern int rl_completion_append_character;],
+  [readline/readline.h],
+  AC_DEFINE(HAVE_RL_COMPLETION_APPEND_CHARACTER, 1,
+  [Define if you have readline 2.2]), )
+fi
+
 # check for readline 4.0
 AC_CHECK_LIB(readline, rl_pre_input_hook,
 	AC_DEFINE(HAVE_RL_PRE_INPUT_HOOK, 1,
diff --git a/pyconfig.h.in b/pyconfig.h.in
index dd52efb..922147e 100644
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -333,6 +333,9 @@
 /* Define to 1 if you have the `readlink' function. */
 #undef HAVE_READLINK
 
+/* Define if you have readline 2.2 */
+#undef HAVE_RL_COMPLETION_APPEND_CHARACTER
+
 /* Define if you have readline 4.2 */
 #undef HAVE_RL_COMPLETION_MATCHES