Display of "narrow no-break space" character

[PierGianLuca]

Hi everyone.

I use Emacs with a GUI and monospaced font (DejaVu Sans Mono). Lately I've had to use 
"no-break space" (U+00A0) and "narrow no-break space" (U+202F) very often.

Emacs does a great job distinguishing space from no-break space: the latter is 
shown as an underlined space. However, no-break space and narrow no-break space 
are represented in exactly the same way (underlined space).

Does anyone know of a method to make Emacs use a different glyph for narrow 
no-break space?

I know of whitespace-mode, but that is a bit overkill for my needs, and would 
require a lot of customization because I don't need highlighting newlines, 
EOLs, and so on.

In case the theme used has something to do with this, I use modus-operandi. But 
other themes seem to have the same issue.

Cheers!