[CentOS] libMrm.so.3

I need to install libMrm.so.3 on my computer that has Centos4.3.
However, I am not experienced with Centos4.3 so far. I do not know where
to find this library for Centos4.3 and how to install it. Is there
something like apt? Using system-config-packages I cannot find any
intelligent way to search for programs and package.

Dirk