-Beware: the Perl 5.005 threads model is known to have bugs, for
-example the regular expressions are not thread-safe. The bugs are
-very hard to fix are and therefore the 5.005 threads model is still
-classified as an experimental feature.
+The old Perl 5.005 threads is obsolete, unmaintained, and its use is
+discouraged. If you really want it, run Configure with the
+-Dusethreads -Duse5005threads options as described in INSTALL.
+
+Either thread model is going to work only in Tru64 4.0 and newer
+releases, older operating releases like 3.2 aren't probably going
+to work properly with threads.
+
+=head2 Long Doubles on Tru64
+
+You cannot Configure Perl to use long doubles unless you have at least
+Tru64 V5.0, the long double support simply wasn't functional enough
+before that. Perl's Configure will override attempts to use the long
+doubles (you can notice this by Configure finding out that the modfl()
+function does not work as it should).
+
+At the time of this writing (June 2002), there is a known bug in the
+Tru64 libc printing of long doubles when not using "e" notation.
+The values are correct and usable, but you only get a limited number
+of digits displayed unless you force the issue by using C<printf
+"%.33e",$num> or the like. For Tru64 versions V5.0A through V5.1A, a
+patch is expected sometime after perl 5.8.0 is released. If your libc
+has not yet been patched, you'll get a warning from Configure when
+selecting long doubles.