TOS QOS on CentOS - seems unable to be set

Hi all,

Running Asterisk 1.2.3 on Centos 4.1

In sip.conf, in the general section tos = 0xB8
because we are running in a cisco DiffServ environment.

During call setup, there is an error message in the log file:
rtp.c: Unable to set TOS to 184

184 is the correct number. Is this a CentOS problem, in
that it won’t let the setsockopt command set the IP_TOS bits?

Thanks