As syphilis mentioned, the link errors are because Data::Alias digs a fair bit into perl's guts to do its job. It meddles with lexer state, modifies the PL_check array, and do various other things that are no doubt considered big "no-no"s. :-)
in reply to From whence comes perl-5.8.6-smartmatch.tar?
Work-arounds are using cygwin or recompiling perl with an augmented list of exported symbols.
I've also been pondering if there's some rude way for me to manually resolve those symbols are runtime, even if they're not exported. I'd need to dig a bit into what object formats and linkage are like on Win32.