error - driver -- postgresql 7.4.2 --Suse 9.0

greetings

I have the following error when connecting from tomcat, appears to me:

Err no se puedo cargar el driver en DefinitionConnectionPortal -->
DefinitionConnectionPortal Cannot create PoolableConnectionFactory
org.apache.commons.dbcp.SQLNestedException: Cannot create
PoolableConnectionFactory, cause:
Connection refused. Check that the hostname and port is correct, and that
the postmaster is running with the -i flag, which enables TCP/IP
networking.
at org.postgresql.Connection.openConnection(Connection.java:136)
at org.postgresql.Driver.connect(Driver.java:122)
at
org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:82)
at
org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:300)
at
org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:838)
at
org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:821)
at
org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:518)

driver that we used is: jdbc7.1-1.2.jar

thanks

Tania Gutierrez