what version of Postgis should i install for Postgres-8.1.5 RHEL 4 -AS RPM

what version of Postgis should i install for Postgres-8.1.5 ??

And where can i find its RPM for RHEL 4 -AS ...???

Thanks in advance

--
Sandeep Kumar Jakkaraju
WeBlog:
http://jakkarajus.blogspot.com