Why am I getting errors from perfmon and PAPI on my Redhat kernels?
Redhat broke the perfmon kernel interface in their kernels and thus only enabled it for root. In some kernels, its disabled entirely. You can test this by running your papi as root, if it then works, guess what, you have a broken kernel. The fix is supposed to be in the latest update to RHEL3 and RHEL4. The best thing to do would be to download a kernel.org kernel, rebuild and go.