Incorrect Thumbnail sizes generated...

In the Product Module, entering a value in the "Image Width" field and nothing or 0 in the "Image Height" field does not generate the correct size thumbnail. It should generate a thumbnail that is only as wide as the field, but it instead generates a thumbnail that is that tall, not wide, regardless of the value in "Image Height". The folder name is not correctly generated either

Example:
Original Image - 350w x 500h
Set Image Width: 200
Set Image Height: (blank)
Image thumbnail generated: 140w x 200h
Folder name: thumbnail 200x200

SHOULD Generate thumbnail 200w x ~286h (+/-)

I have tested the above and several variations while clearing the thumbnail folders.

HOWEVER, the above example works correctly when setting Thumbnail/Image size in the System Configuration. The correct proportion thumbnail is generated and folder properly named when using just 106 in the width (generates an image 106w x 151h).