Quanta is too slow

[Grégoire Cachet <zwiffer@zwiffer.org>]

hello

I use kde 3.1 and quanta debs from 
deb http://shakti.ath.cx/debian/kde3.1/ ./

I have a problem with quanta which is very slow when I edit a page that
contains about more than 250 lines. Quanta becomes very slow and
unusable. For example it takes about 5 seconds to write one caracter
when there is a CSS stylesheet of 600 lines
However I have no problem with spaces and breaklines. Moreover, there
isn't any problem while I edit the same file with kwrite.

How can I solve the problem ?

my system is K7-750, 256Mo SDRAM and GeForce256 DDR 3d card (nvidia
drivers are installed and work)

thanks

grégoire