1) Get Valgrind source code from SVN using revision 9648 and 1888 for VEX
svn co -r 9648 svn://svn.valgrind.org/valgrind/trunk
cd VEX
svn update -r 1888
2) Download the patch here http://bugsfiles.kde.org/attachment.cgi?id=32348
3) Apply the patch into the source code
cd valgrind
patch -p1 < [path to the patch]
4) Run autogen.sh to run autotools
5) Configure the source code
./configure --host=arm-angstrom-linux-gnueabi
The patch still has some bugs such as CPU instruction alignment you can 'cat /proc/cpu/alignment' to find out if the kernel is configured to fix unaligned accesses, and you can enable it by executing 'echo 2 > /proc/cpu/alignment' but it's enough to use for simple application.
Have fun with Valgrind :-)