Help! Need to turn a 16x9 image 9x16

[BobsUrUncle]

For the most part, most projectors on the market don't like to do this (turned on their side, that is).

I have a space that we have a 25' vertical white wall painted with goo. We currently have a dp DLP projector hung from the ceiling, but with an image processor in front of the VGA input, rotating the image, and it looks like crap. We are using this to project moving video, as well as digital signage info. Our head-end is capable of up to 1080p resolution.

Is there an attachment we can put on the front of the lens to rotate the image 90 degrees so we can display in full resolution?