Problem w/ IDENT authentication

I am trying to set up IDENT authentication for Tomcat 5 on my Fedora
Core 2 system.  I've added the appropriate line to pg_hba.conf:

host    tomcat4 tomcat4 127.0.0.1       255.255.255.255 ident   sameuser

This works as expected from a console:

     [root@home webapps]# su tomcat4
     sh-2.05b$ psql -h localhost tomcat4
     Welcome to psql 7.4.2, the PostgreSQL interactive terminal.

     Type:  \copyright for distribution terms
            \h for help with SQL commands
            \? for help on internal slash commands
            \g or terminate with semicolon to execute query
            \q to quit

     tomcat4=>

In my servlet I try to get a connection:

     db = DriverManager.getConnection("jdbc:postgresql:tomcat4",
             "tomcat4", "");

And I get the following:

     org.postgresql.util.PSQLException: A connection error has occurred:
     org.postgresql.util.PSQLException: FATAL: IDENT authentication
     failed for user "tomcat4"

I've verified that the servlet does run as tomcat4 by writing a
temporary file.

TIA for any ideas!

--
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Ian Pilcher                                        i.pilcher@comcast.net
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