Help with <fieldset> encapsulation within css page?

Gentlemen;

I'm in the process of migrating several pages from HTML under frames to
noframes using css using the three or four box design.

For most of my efforts its going well. However, one area that's giving me a
lot of grief is where I've encountered the user of <fieldset>. Whereas in
the HTML use the box drawn by this tag simply encapsulates the elements
contained, on the css controlled page the box drawn uses the maximum width
of the current DIV section, in essence, the entire width of the page less
any side box(es).

I thought this would be an HTML issues so I tried in that group first but
the advise was to try this group. What follows is a snippet of some
example code:

<div class=\"center\">
<fieldset class=\"indent2\">
<legend>Select Test Results to View</legend>
<form name=\"getID\" method=\"post\" action=\"sc00g2.php?s=1\">
<table align=\"center\">";
/* Generate Test Selection Prompt */
print "<tr><td align=\"center\">
<select name=\"_qzuid\">
<option value=\"-1\">_Select Desired Test_</option>";