make sure there are no blank spaces after the closing php tags, for example:
"<?php require_once( "../WA_Globals/WA_Globals.php" ); ?> "
or:
"<?php require_once( "../WA_SecurityAssist/Helper_PHP.php" ); ?> "
also make sure there are no blanlines between php code blocks such as:
"<?php require_once( "../WA_Globals/WA_Globals.php" ); ?>
<?php require_once( "../WA_SecurityAssist/Helper_PHP.php" ); ?>"
If you are still having problems send a copy of the page so I can examine the code.