Sorry, I wasn't clear. I don't mean embedding the fonts, I know how to do it.
My problem is with installing/using the fonts in the reader (not on an ebook file). My reader allows to just copy the font files in the device, and then I can choose whichever font I like as my "default" text font. With other fonts, I copy the regular, bold, italic and bold-italic files, and it works as expected (a single entry in the font selection menu, displayed with the regular variant). With this font, however, once I edit the family names in the font files, I get the italic font in the selection menu, and it's the italic that becomes the default text font. It seems that the italic variant is claiming to be the "normal" one in the family.