=head2 Binary Incompatibility
-Perl 5.8 has not been designed to be binary compatible with earlier
-releases of Perl. While the compatibility has not been intentionally
-broken, it has not been intentionally protected, either. The major
-reason for the discontinity is the new IO architecture called PerlIO.
-The PerlIO is the default configuration because without it many new
-features of Perl 5.8 cannot be used. In other words: you just have
-to recompile your modules, sorry about that.
+B<Perl 5.8 is not binary compatible with earlier releases of Perl.>
+
+B<You have to recompile your XS modules.>
+
+(Pure Perl modules should continue to work.)
+
+The major reason for the discontinity is the new IO architecture
+called PerlIO. The PerlIO is the default configuration because
+without it many new features of Perl 5.8 cannot be used. In other
+words: you just have to recompile your modules, sorry about that.
In future releases of Perl non-PerlIO aware XS modules may become
completely unsupported. This shouldn't be too difficult for module
authors, however: PerlIO has been designed as a drop-in replacement
(at the source code level) for the stdio interface.
+Depending on your platform, there are also other reasons why
+we decided to break binary compatibility, please read on.
+
=head2 64-bit platforms and malloc
If your pointers are 64 bits wide, the Perl malloc is no longer being