diff --git a/bootstrap b/bootstrap
index 56f507b..f3109fd 100755
--- a/bootstrap
+++ b/bootstrap
@@ -29,8 +29,8 @@ fi
 # Check for needed features
 auxdir="`sed -ne 's/^[ \t]*A._CONFIG_AUX_DIR *([[ ]*\([^] )]*\).*/\1/p' $conffile`"
 pkgconfig="`grep '^[ \t]*PKG_PROG_PKG_CONFIG' $conffile >/dev/null 2>&1 && echo yes || echo no`"
-libtool="`grep '^[ \t]*A._PROG_LIBTOOL' $conffile >/dev/null 2>&1 && echo yes || echo no`"
-header="`grep '^[ \t]*A._CONFIG_HEADER' $conffile >/dev/null 2>&1 && echo yes || echo no`"
+libtool="`grep '^[ \t]*LT_INIT' $conffile >/dev/null 2>&1 && echo yes || echo no`"
+header="`grep '^[ \t]*A._CONFIG_HEADERS' $conffile >/dev/null 2>&1 && echo yes || echo no`"
 makefile="`[ -f Makefile.am ] && echo yes || echo no`"
 aclocalflags="`sed -ne 's/^[ \t]*ACLOCAL_AMFLAGS[ \t]*=//p' Makefile.am 2>/dev/null || :`"
 
diff --git a/build/win32/config.h b/build/win32/config.h
index f909547..b3454d0 100644
--- a/build/win32/config.h
+++ b/build/win32/config.h
@@ -75,7 +75,6 @@
 #define PACKAGE_URL "http://caca.zoy.org/wiki/libcaca"
 #define PACKAGE_VERSION "0.99.beta20"
 /* #undef PROF */
-/* #undef RETSIGTYPE */
 /* #undef SCREENUPDATE_IN_PC_H */
 #define STDC_HEADERS 1
 /* #undef USE_COCOA */
diff --git a/caca/driver/ncurses.c b/caca/driver/ncurses.c
index f0b4e3e..326ae7a 100644
--- a/caca/driver/ncurses.c
+++ b/caca/driver/ncurses.c
@@ -188,7 +188,7 @@
  */
 
 #if defined HAVE_SIGNAL
-static RETSIGTYPE sigwinch_handler(int);
+static void sigwinch_handler(int);
 static caca_display_t *sigwinch_d; /* FIXME: we ought to get rid of this */
 #endif
 #if defined HAVE_GETENV && defined HAVE_PUTENV
@@ -594,7 +594,7 @@ static void ncurses_set_cursor(caca_display_t *dp, int flags)
  */
 
 #if defined HAVE_SIGNAL
-static RETSIGTYPE sigwinch_handler(int sig)
+static void sigwinch_handler(int sig)
 {
     sigwinch_d->resize.resized = 1;
 
diff --git a/caca/driver/slang.c b/caca/driver/slang.c
index 6cf5fa1..ccd4474 100644
--- a/caca/driver/slang.c
+++ b/caca/driver/slang.c
@@ -102,7 +102,7 @@ static void slang_init_palette(void);
 static void slang_write_utf32(uint32_t);
 
 #if defined(HAVE_SIGNAL)
-static RETSIGTYPE sigwinch_handler(int);
+static void sigwinch_handler(int);
 static caca_display_t *sigwinch_d; /* FIXME: we ought to get rid of this */
 #endif
 #if defined(HAVE_GETENV) && defined(HAVE_PUTENV)
@@ -536,7 +536,7 @@ static void slang_write_utf32(uint32_t ch)
 }
 
 #if defined(HAVE_SIGNAL)
-static RETSIGTYPE sigwinch_handler(int sig)
+static void sigwinch_handler(int sig)
 {
     sigwinch_d->resize.resized = 1;
 
diff --git a/configure.ac b/configure.ac
index 905b3a0..458e949 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,13 +1,13 @@
 
-AC_INIT(libcaca, 0.99.beta20)
-AC_PREREQ(2.50)
+AC_INIT([libcaca],[0.99.beta20])
+AC_PREREQ([2.71])
 AC_CONFIG_AUX_DIR(.auto)
-AC_CANONICAL_SYSTEM
+AC_CANONICAL_TARGET
 AM_INIT_AUTOMAKE([no-define tar-ustar silent-rules subdir-objects])
 dnl AM_MAINTAINER_MODE
 AM_DEFAULT_VERBOSITY=0
 
-AM_CONFIG_HEADER(config.h)
+AC_CONFIG_HEADERS([config.h])
 
 LT_MAJOR="0"
 LT_MINOR="99"
@@ -28,13 +28,11 @@ AC_SUBST(OBJC)
 AC_SUBST(OBJCFLAGS)
 AM_PROG_AS
 
-AC_LIBTOOL_WIN32_DLL
-AM_PROG_LIBTOOL
-AC_LIBTOOL_CXX
+LT_INIT([win32-dll])
+LT_LANG([C++])
 
 AC_C_CONST
 AC_C_INLINE
-AC_TYPE_SIGNAL
 
 dnl  AC_PROG_EGREP only exists in autoconf 2.54+, so we use AC_EGREP_CPP right
 dnl  now otherwise it might be set in an obscure if statement. Same thing for
@@ -139,19 +137,28 @@ fi
 AC_SUBST(GETOPT_LIBS)
 
 AC_MSG_CHECKING(for Sleep)
-AC_TRY_COMPILE([#include <windows.h>],[Sleep(42);],
+AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+   [[#include <windows.h>]],
+   [[Sleep(42);]])],
  [AC_MSG_RESULT(yes)
   AC_DEFINE(HAVE_SLEEP, 1, [Define to 1 if you have the ‘Sleep’ function.])],
  [AC_MSG_RESULT(no)])
 
 AC_MSG_CHECKING(for fsin/fcos)
-AC_TRY_COMPILE([],[double x; asm volatile("fsin; fcos":"=t"(x):);],
+AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+   [[]],
+   [[double x; asm volatile("fsin; fcos":"=t"(x):);]])],
  [AC_MSG_RESULT(yes)
   AC_DEFINE(HAVE_FSIN_FCOS, 1, [Define to 1 if you have the ‘fsin’ and ‘fcos’ instructions.])],
  [AC_MSG_RESULT(no)])
 
 AC_MSG_CHECKING(for fldln2/fxch/fyl2x)
-AC_TRY_COMPILE([],[double x; asm volatile("fldln2; fldln2; fxch; fyl2x":"=t"(x):);],
+AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+   [[]],
+   [[double x; asm volatile("fldln2; fldln2; fxch; fyl2x":"=t"(x):);]])],
  [AC_MSG_RESULT(yes)
   AC_DEFINE(HAVE_FLDLN2, 1, [Define to 1 if you have the ‘fldln2’ and other floating point instructions.])],
  [AC_MSG_RESULT(no)])
@@ -404,11 +411,8 @@ ac_cv_my_have_cxx="no"
 if test "${enable_cxx}" != "no"; then
   AC_MSG_CHECKING([working <iostream>])
   AC_LANG_PUSH(C++)
-  AC_TRY_COMPILE(
-   [#include <iostream>],
-   [],
-   [ac_cv_my_have_cxx="yes"
-    CACA_BINDINGS="${CACA_BINDINGS} C++"])
+  AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <iostream>]], [[]])],[ac_cv_my_have_cxx="yes"
+    CACA_BINDINGS="${CACA_BINDINGS} C++"],[])
   AC_LANG_POP(C++)
   AC_MSG_RESULT([$ac_cv_my_have_cxx])
 fi
diff --git a/src/cacaserver.c b/src/cacaserver.c
index 825c3d4..d875c05 100644
--- a/src/cacaserver.c
+++ b/src/cacaserver.c
@@ -115,7 +115,7 @@ struct server
     int client_count;
     struct client *clients;
 
-    RETSIGTYPE (*sigpipe_handler)(int);
+    void (*sigpipe_handler)(int);
 };
 
 static void manage_connections(struct server *server);