correct way to install contrib packages

How is one supposed to install the  postgresql
contrib packages in an RPM based system? (sorry for starting with a question )

I did the following.
1.  Built the binary rpms from source rpms as described in README(s)
2.   rpm -Uvh *.rpm   (for all the binary rpms , including postgresql-contrib)
3. cd /usr/lib/pgsql/contrib/<somepackage>
4. psql -U postgres template1  -f  package.sql

The problem is in the <package>.sql file there is a $libdir variable  ,
which unless changed to  value of `pwd`
refuses to load becoz it cant find the .so files!
was it the proper way ??

also in case ot tsearch contrib module i had to manually link
libtsearch.so to tsearch.so  to load the contrib package.

regds
Rajesh Kumar Mallah.