I struggled to find a solution for your problem. Evern went so far as to install Nyditot, but it did not solve the problem.
A little freeware app may be of interest to you.... i.e. RBC9-Landscape 1.0
I tried it out on my Mogul and it works like a charm.
http://handheld.softpedia.com/get/Ot...pe-40862.shtml
When run, it places an icon in the tray at the bottom of the Today screen (two versions are available Left and Right, only run the one you need). When run the screen switches to landscape mode in the configuration picked i.e. Left or Right. When you open the Keyboard the device stays in Landscape mode, when you close the keyboard it changes back to Portrait mode, but a simple click on the icon at the bottom of the Today screen will rotate back to Landscape without needing to open Settings etc. I am attaching the Zip file for your convenience. Copy one of the exe files to your Windows/Startup folder on your device and see if it works.
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