I don't know if this is already possible. If so, just forget my question.
Look at the Simple Machines' SMF 1.1.4, they have it implemented, working example is
here:
http://mbreg.de/forum/index.php?action=unreadreplies
Anyway, i miss this feature since long at wikipedia, where i am used to read up texts
heavily and i always regret there's only so small space left on non-wide-screens,
netbooks, PDAs, or when you need huge fonts (working from a distance).
What do you think about it ?
Greets, Micha