Using pgAgent w/o pgAdmin3 on linux

Dear all,

our company bought some software which uses a 3rd party postgresql 8.3.8 on linux Centos 5.6
We want to use pgAgent to extend some functionality in the database. Now, obviously don't need a GUI, so I figured I don't need to install pgAdmin3. I downloaded: pgAgent-3.0.0-Linux.tar.gz

I got to the point where I am trying to run the service pgAgent wirth a startup script and installed pgAgent catalog in the postgres database of the postgresql instance. When trying to run the service I get:
Starting PgAgent: pgagent: error while loading shared libraries: libssl.so.0: cannot open shared object file: No such file or directory
[FAILED]

I am using a startup script from postgresonline.com: http://www.postgresonline.com/journal/archives/86-Yum-addendum-for-8.3.5-and-PgAgent.html

So I dont have a postgresql instance installed as you would do with yum install. I dont have pgAdmin installed and can't seem to find it in the default repositories: yum list pg* comes out blank. I downloaded and tried to install: pgadmin3-1.8.4-1.rhel5.x86_64.rpm
but it is complaining:
error: Failed dependencies:
libwx_baseu-2.8.so.0()(
etc etc

I have considered adding the libs one by one as you progress, but i want to have a nice and clean solution :)

Thanks in advance.

With kind regards,
Daniel