hi any news to this .. since 2.71 till now im encountering this error .. sometimes new remap keys are reverting back to original .. not only the Duplicate function
i think this should be prioritize creating preset at input editor will useless

the only temporary fix solution for this is to
Use the Blender Preset from start > Modify It >
and dont Use + to create a Preset or the Import / Export because when i do as time passes creating multiple presets for tests .. it overlaps with blender keys or sometimes it will magically forgets the key ..

anyway ... yes it fixes the bug .. but im worried how i can backup my keys if im using the Blender Modified Preset ( as far as i know the blender default keys cant be copied ive search here )

C:\Program Files\Blender Foundation\Blender\2.72\scripts\presets\keyconfig
Only Maya and Max Are Available

C:\Users\Hiroka Matsuiko\AppData\Roaming\Blender Foundation\Blender\2.72\scripts\presets\keyconfig

the keyconfig or py only appear if i use + sign or Import a Hotkey
as i said im avoiding export/import nor the + sign because the bug will trigger

hope this information helps

this is my current blender right now all keys has been modified .. the workflow or shortcut keys is not Blender default

the bug doesnt trigger for now

I hope that this will be fix in 2.73
thank you

@Seb Rena (rattle-snake), T42521 and this have the same root, even if it doesn't seem so at a first glance.