I don't know about Strawberry, but in vanilla perl 5.10.0 you can use smart matching without any use feature directive. This was wrongly documented in older development versions, but should be fixed now. (If it isn't, please tell us where you read that). 
$ perl5.10.0 --version

This is perl, v5.10.0 built for i486-linux-gnu-thread-multi
[...]
$ perl5.10.0 -wle 'print "YaY" if "a" ~~ m/./'
YaY

[download]

Update: I found the doc patch that fixed perlsyn.

In reply to Re: Smart match operator support in Strawberry perl 5.10.0.1 by moritz
in thread Smart match operator support in Strawberry perl 5.10.0.1 by jds17

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.