John,

Check out the detailing DIY articles on MercedesShop (there is a link at the top of your sceen). They recommend using distilled white vinegar to remove the water spots. Since this will remove the wax you will need to re-wax these areas.

There is alot of usefull information in the detailing DIY articles.

__________________
Ray
1998 Mercedes E320, 200K Miles
2001 Acura 3.2TL, 178K Miles
1992 Chevy Astro, 205K Miles