I get the following when I run tinyproxy: Could not create the pool of children

various posts on the net say enable shared memory in the kernel, etc.  I'm running Ubuntu 9.04 on the sheevaplug.  Any ideas?

root@debian:~# sysctl -a | grep shmmax
error: permission denied on key 'net.ipv4.route.flush'
kernel.shmmax = 33554432

(the above matches the size I see on my desktop system)

Thanks,
Cliff