your page is using the virtual() function for including files:
<?php virtual( "/pges/webassist/security_assist/helper_php.php" ); ?>
instead of require once. this will happen if you set the "Create Links Relative To" option in the Dreamweaver site definition to "Site", using "Document" will cause Dreamweaver to use the require_once function.
There are a couple problems with using the virtual function:
1) The virtual function is only avail;able on apache servers.
2) When the virtual function is used, it writes a bit to the document header which generates the Headers Already Sent error on trying to redirect.
I recommend setting the "Create Links Relative To" option Document so that includes will use the require_once() function to prevent these issuers