Added code to reset the RESPONSE content-type after calling

manage_page_style.css. Otherwise, pages don't display on Netscape
4. :(

lib/python/App/dtml/manage_page_header.dtml

@@ -13,7 +13,7 @@
 <!--
 
 <dtml-var manage_page_style.css>
-
+<dtml-call "RESPONSE.setHeader('Content-Type','text/html')">
 -->
 </style>
 <dtml-else>