The speakup patch is to be applied to unmodified 2.6.21.5
kernel sources (though it may also work with later kernels)

Untar the kernel source in this directory in /usr/src, and
then apply the patch:

cd linux-2.6.21.5
zcat ../speakup-cvs-20070303.diff.gz | patch -p1
make

On newer kernels, "make oldconfig" may be needed prior to
"make", or "make menuconfig" if you have kernel options
that you'd like to change.

Enjoy!  :-)

Pat