The situation is that though the kernel SIGRTMIN is still 32 on most
platforms, glibs defines SIGRTMIN and SIGRTMAX as functions calls.
Currently, SIGRTMIN is 34, but the man page may not mention it; the
value can change with a new build of glibc (even though the binary of
the caller has not changed).
[Thanks to Jakub Jelinek, for explaining this to me.]

--- man-pages-2.55/man7/signal.7.sig	2007-05-12 15:12:02.000000000 +0200
+++ man-pages-2.55/man7/signal.7	2007-06-20 13:21:12.000000000 +0200
@@ -34,8 +34,10 @@
 .\" 2004-12-03, Modified mtk, added notes on RLIMIT_SIGPENDING
 .\" 2006-04-24, mtk, Added text on changing signal dispositions,
 .\"		signal mask, and pending signals.
+.\" 2007-06-19, Stepan Kasal (skasal@redhat.com), modified
+.\"		description of real-time signals
 .\"
-.TH SIGNAL 7  2002-06-13 "Linux 2.4.18" "Linux Programmer's Manual"
+.TH SIGNAL 7  2007-06-19 "Linux 2.6" "Linux Programmer's Manual"
 .SH NAME
 signal \- list of available signals
 .SH DESCRIPTION
@@ -226,13 +228,13 @@
 .SS "Real-time Signals"
 Linux supports real-time signals as originally defined in the POSIX.1b
 real-time extensions (and now included in POSIX.1-2001).
-Linux supports 32 real-time signals, numbered from 32
-.RB ( SIGRTMIN )
-to 63
-.RB ( SIGRTMAX ).
-(Programs should always refer to real-time signals using notation
+Linux supports real-time signals numbered from
+.BR SIGRTMIN " to " SIGRTMAX .
+Programs should always refer to real-time signals using notation
 .BR SIGRTMIN +n,
-since the range of real-time signal numbers varies across Unix systems.)
+since the range of real-time signal numbers depends on Linux kernel version
+and on libc build.
+And, of course, it varies across other Unix systems.
 .PP
 Unlike standard signals, real-time signals have no predefined meanings:
 the entire set of real-time signals can be used for application-defined