--- rpl/README	2010/03/17 15:12:37	1.3
+++ rpl/README	2010/04/17 18:57:33	1.4
@@ -18,6 +18,17 @@ this language is a half-compiled high le
 symbolic and scientific computations.
 
 
+  * RPL/2 requires :
+	- nawk or gawk;
+	- libtool 1.5 or newer. To build RPL/2 on Mac OSX, you should have to
+	add libtool m4 path in tools/file-*/configure.ac and
+	tools/file-*/Makefile.am;
+	- gcc-4.2 or newer;
+	- g++-4.2 or newer;
+	- gfortran-4.2 or newer.
+
+	RPL/2 build process invoques automake and autoconf.
+
   * OpenSSL issue :
 
 	OpenSSL does not use any configure script. If build process aborts on
@@ -27,7 +38,7 @@ flags.
 
   * RPL/2 is known to run on :
 
-	- Linux (kernel 2.6.12 and above) on i386, amd64, ppc32, sparc32,
+	- Linux (kernel 2.6.26 and above) on i386, amd64, ppc32, sparc32,
 		sparc64, alpha. Test distribution is Debian. Warning, you have to
 		use NPTL, not LinuxThreads due to a bug in sem_post() that is not
 		async safe.
@@ -36,10 +47,10 @@ flags.
 		64bits executable, you have to modify some generated makefiles or
 		specify some options. See 64bits on Solaris.
 	- FreeBSD 7.x on i386. I have installed a FreeBSD 7.0, upgraded to 7.2
-		 and RPL/2 ran without any trouble. RPL/2 does not run on FreeBSD 8.0
+		and RPL/2 ran without any trouble. RPL/2 does not run on FreeBSD 8.0
 		because sig_into_t struct is not filled. Someone has reported that
 		FreeBSD 7.2 did not filled this struct too...
-	- NetBSD 4.0 and above on sparc32 with a restriction. NetBSD's sigpending
+	- NetBSD 4.0 and above with a restriction. NetBSD's sigpending
 		is broken and it is impossible to use DETACH intrinsic. Bug report
 		has been done and this bug should be fixed in next NetBSD release.
 		Sigpending has been fixed in NetBSD 5.0 and RPL/2 runs fine.
@@ -47,7 +58,7 @@ flags.
   * RPL/2 should run on :
 
 	- HP-UX (10.20 and above), but not tested for a long time.
-	- Linux (2.6.12 and above) on ppc64 and other hardware (arm, hppa...) or
+	- Linux (2.6.26 and above) on ppc64 and other hardware (arm, hppa...) or
 		with other distributions than Debian.
 	- FreeBSD 7.0 and above on other architecture than i386. Please not
 		that I cannot reproduce sig_info_t bug and I do not have more
@@ -62,7 +73,8 @@ flags.
 
 	- OpenBSD due to a major bug in sigaltstack syscall when a program is
 		linked with -lthread. As this bug comes from OpenBSD libraries,
-		OpenBSD port has to wait for a fixed sigaltstack.
+		OpenBSD port has to wait for a fixed sigaltstack. RPL/2 uses pselect()
+		that is unavailable too.
 	- OpenVMS (work in progress) on Alpha and Integrity due to some bugs in GNV.
 		RPL/2 never works on OpenVMS VAX because GNV is too old on this
 		architecture.
@@ -84,7 +96,7 @@ flags.
 	several systems, some Posix libraries have strange 'features'...
 
 	On all systems, you must install GNU make and you should install
-	gcc/g++/gfortran (minimal release : 4.0.0). It is possible to build
+	gcc/g++/gfortran (minimal release : 4.2.0). It is possible to build
 	RPL/2 with some other compilers (for example cc and f95 from SunStudio,
 	or cc and f95 from Digital^WCompaq^WHP) but I do not test all potential
 	combinaisons.