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(at)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(dot)pilcher(at)comcast(dot)net
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