While I've not dug into it in any depth, odds are you're getting bit by a bug in perl's pad caching.
When you go recursive on a sub, it triggers a more aggressive caching scheme for the lexical pad for a sub, and it looks like as part of that a top-level pad's not getting cleaned up when it ought to be. (It's also possible this is triggering a cleanup delay/bug in the top-level pad)
If you can, try boiling this down as small as possible and fire it off as a bug report with perlbug.
Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
Want more info? How to link or
or How to display code and escape characters
are good places to start.