FMS3 on RHEL 4 needs which nspr library?

When I do the install for FMS3, I get the following error message:

NPTL 2.3.4
Starting Adobe Flash Media Server (please check /var/log/messages)
Error: Flash Media Server needs the NSPR library installed.

There are no errors, either in the logs in /opt/adobe/fms/logs or in /var/log/messages and the mozilla-nspr libraries are installed:

[root@bbap2 FMS_3_0_1_r123]# up2date --dry-run mozilla-nspr

Fetching Obsoletes list for channel: rhel-i386-as-4...

Fetching rpm headers...
########################################

Name Version Rel
----------------------------------------------------------
mozilla-nspr 1.7.13 1.4.1 i386


Testing package set / solving RPM inter-dependencies...
########################################

Name Version Rel
----------------------------------------------------------


The following packages you requested are already updated:
mozilla-nspr

Now, I can see two things to try. I could install the seamonkey-nspr libraries, but I have no reason to think they'd be any better than the mozilla-nspr libraries, or I could install the nspr libraries, but they're marked BETA for RHEL 4.

I haven't yet tried running the server, and maybe everything is just fine, but I'd still like to hear other folks' experiences.