Lets Go Digital took a look at the waterproof Optio WPi from Pentax which features a six megapixel CMOS and three times optical zoom, here's a small quote from their test report:

While the previous model, the Optio WP, offers 5 Megapixels of resolution, Pentax equipped the WPi digital camera with an image sensor of 6.36 Megapixels offering 6.0 effective Megapixels. The built-in lens features a 3x optical zoom with a range of 38mm to 114mm, rather standard I'd say. Thanks to the internal optical zoom lens Pentax was able to make the camera waterproof. The lens is protected by a glass element that has to be kept clean thoroughly to prevent smudgy photos. Striking is the fact that the tiny zoom lens consists of 11 elements in 9 groups, 3 of which are aspherical elements which is certainly great.



Link: Lets Go Digital