seems like some bugs in mesa 6.5
https://bugs.freedesktop.org/show_bug.cgi?id=7208
https://bugs.freedesktop.org/show_bug.cgi?id=6624
but fixed in CVS now
let's wait for the new release:)

here is the "about:buildconfig" produced by firefox1.5 from mozilla offical website
It performs perfect in my gentoo.


about:buildconfig

Build platform
target
i686-pc-linux-gnu

Build tools
Compiler Version Compiler flags
gcc gcc version 3.3.2 20031022 (Red Hat Linux 3.3.2-1) -Wall -W -Wno ...

It takes about one or two seconds to swith between tabs
and often lags when opening a new page.
I built it with default USE flags

here is my "about:buildconfig"

about:buildconfig

Build platform
target
i686-pc-linux-gnu

Build tools
Compiler Version Compiler flags
i686-pc-linux-gnu-gcc gcc ...