Thank you for this bug report. To properly diagnose the problem, we
need a short but complete example script to be able to reproduce
this bug ourselves. 

A proper reproducing script starts with <?php and ends with ?>,
is max. 10-20 lines long and does not require any external 
resources such as databases, etc. If the script requires a 
database to demonstrate the issue, please make sure it creates 
all necessary tables, stored procedures etc.

Please avoid embedding huge scripts into the report.

my source code is shown on these two webpages
http://taith.divinedesigns.ca/bug.php
http://taith.divinedesigns.ca/bug2.php

Please provide SHORT but COMPLETE reproduce code. Some comments in the code with expected and actual results are appreciated.

<?
function shownavs(){
 global $allnavs, $blocknavs, $head, $autokey;

 if(isset($allnavs)){
  $navsoutput .= '<table>';
  foreach($allnavs as $group => $i){
   $title = $group;
   foreach($i as $name => $link){
    if(isset($link)){
     $content .= '<br>'.$name; #this line usually has same issue, altered for bug report
    }
   }
   $text .= '<tr><td>'.set_collapse($title,$content,$group).'</td></tr>';
   unset($content);
  }
  $navsoutput .= $text.'</table>';
 }
 return $navsoutput;
}

function set_collapse($title,$text,$name){
 global $collapsenum, $css, $head;
 if(!isset($collapsenum)){
  $collapsenum = "1";
  $head .= '<script language="javascript">
var ie4 = false;
if(document.all){
 ie4 = true;
}

function getObject(id){
 if(ie4){
  return document.all[id];
 }else{
  return document.getElementById(id);
 }
}

function toggle(link, divId, Name){
 var lText = link.innerHTML;
 var d = getObject(divId);
 if(lText == \'+\'){
  link.innerHTML = \'-\';
  d.style.display = \'block\';
  document.cookie = Name + "=shown";
 }else{
  link.innerHTML = \'+\';
  d.style.display = \'none\';
  document.cookie = Name + "=hidden";
 }
}
</script>'; # it should be returning this outside of both the functions
 }
 return '<table cellspacing=0 width="50%" class=collapse>
 <tr class=collapsetitle>
  <td class=navtitle>[<a title="Show/Hide" class=toggle href="javascript: void(0);" onclick="toggle(this,\''.$key.'\',\''.$name.'\');">'.$h.'</a>]'.$title.'</td>
 </tr>
 <tr id="'.$key.'" class="'.$hidden.'">
  <td>'.$text.'</td>
 </tr>
</table>';
}

$allnavs[test]=test.php
$body = shownavs();
echo $head;
echo $body;
?>

these functions work perfectly well when used on their own... but not so when combined...

Sorry, but your problem does not imply a bug in PHP itself.  For a
list of more appropriate places to ask for help using PHP, please
visit http://www.php.net/support.php as this bug system is not the
appropriate forum for asking support questions.  Due to the volume
of reports we can not explain in detail here why your report is not
a bug.  The support channels will be able to provide an explanation
for you.

Thank you for your interest in PHP.

Please use php-general@lists.php.net for such problems. Thank you.