If lost or in case of doubt, please collect information to describe your problem in detail and direct questions and requests for help on XRPS to the XMM Helpdesk. Feedback, i.e., suggestions and/or criticism, should also be sent to the XMM Helpdesk. For details on XMM Helpdesk services and mailing lists, please consult the XMM Helpdesk web page, at the URL http://astro.estec.esa.nl/XMM/news/xmmhelp_top.html.