Zaino Glass polish should do the trick.... I experimented with it on my uncles van... apparently he doesn't know the value of drying your car! so he basically had waterspots like mad... Zaino+ a little bit of elbow grease, should take it right off.
2001 Granite Green EX-L
1999 Toyota Tacoma
1998 Toyota Camry
One more question. In the description of Z-12 Glass Polish it says not to use on coated glass. I didn't know if this meant factory privacy glass so I e-mailed Sal. His answer was to try a test spot. I havn't ordered it yet and was wordering if anyone knew if coated glass means privacy glass or aftermarket tinting?