I am trying to install WordPerfect 5.1 on a Windows 7 through DOSBOX, and so far I managed to make everything work as intended, but now I am facing a weird issue.

When I have Capslock on, all letters come out as uppercase, EXCEPT for e, y, u, i, o, c and n, which always come on lower case, no matter the capslock state. They only appear as upper case if I use shift to input them.

Obviously these are letters which can take accents on an international keyboard (and I'm using the "ux" keyboard layout for DOSBOX), but the accents come out fine (both upper and lower case) if I use them with shift (except for upper case Ó ["O"+acute accent], which does not show up at all).

I have been searching for a lead or solution to this for a couple days no, and so far have not found any reference to this. Any clues?