xemacs and oversized characters

I've just fixed a bug in my X server, so that it correctly displays characters whose ink extends outside the font ascent/descent. Of course, this has now raised the question of how XEmacs should deal with such characters. At present, it uses (I say this based on observation, not source inspection) the font ascent to determine the line spacing. Hence, if I write (where Acircumflex denotes the appropriate character) foo Acircumflex in -adobe-courier-medium-r-normal--12-*-*-*-m-*-iso8859-1 then the top of the circumflex protrudes into the territory of the f. (The font_ascent is 10, but the character is 11 pixels high.) So when I delete the Acircumflex, the top of the circumflex is left behind, creating an annoying fly speck. (As a side issue, XEmacs is already very prone to fly specks, even without this rather perverse case. Are there redisplay experts who are working on it, or should I think about becoming a redisplay expert---I hope not the latter, since the redisplay code is the most frightening thing I've seen since gcc!) What should XEmacs do? I can see two obvious options: (1) XEmacs should treat outsize characters as it treats any other random glyph, and increase the line height accordingly. (2) XEmacs should continue to use the font_ascent to determine line spacing, and redisplay needs to redisplay the area into which an outsize character extends. Leaving aside the fact that (1) is much easier than (2), it's not clear to me what the *right* thing to do is. Anybody feel like worrying about it?