I just pulled 2.91 and I get the same results as you. 

C:\test>perl -mCGI -le"$q=new CGI; print $CGI::VERSION; $CGI::XHTML=1;
+ print $q->br;"
2.91
<br></br>

[download]

I even tried explicitly setting $CGI::XHTML = 1; directly--even though it appears to be set to this at line 45 of CGI.pm, and the only place where I can see that it gets modified is at line 718 as a result of the -no_xhtml option. The code generating the BR markup 

1948  $break = $XHTML ? "<br />" : "<br>";
2116  $break = $XHTML ? "<br />" : "<br>";

[download]

looks like it ought to do the right thing.

Upshot: I guess it's time to send Lincoln Stein a bug report. You could try for a patch as well, but I'm scuppered if I can see where to patch:)

Examine what is said, not who speaks.
1) When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
2) The only way of discovering the limits of the possible is to venture a little way past them into the impossible
3) Any sufficiently advanced technology is indistinguishable from magic.
Arthur C. Clarke.

In reply to Re: Re: Re: br tag in CGI.pm V2.91 by BrowserUk
in thread br tag in CGI.pm V2.91 by cLive ;-)

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.