If you really wanted to use regex, you can use it to narrow the dictionary list before preformming one of the above (most notably Zaxo's) methods. 
  my $jumble = 'RTESAMCNA';
  open FILE, "/usr/share/dict/words";
  my $n = length $jumble;
  my @possible_words = grep /^[$jumble]{$n}$/i, map {chomp; $_} <FILE>
+;
  close FILE;

[download]
This narrows (with the dictionary i have) the list for "RTESAMCNA" down to just 35 words. From there, you can use the lc/split/sort/join & hash method to get the final list (for example, it finds 'treatment', but clearly that should be excluded). Obvisouly the longer the jumble, the better off this initial pass is.. (And depends on the letter combinations, too)

In reply to Re: regex for word puzzle by davidrw
in thread regex for word puzzle by Anonymous Monk

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.