JDBC: java.sql.SQLException: results returned

Hackers,

I get the following error (see below) when I attempt to insert a row into
one of our tables. I'm using postgres 6.4 with java/jdbc 1.2.1.

Any ideas on what it means? I can't seem to find documentation
on this particular exception anywhere?

Thanks,

Eric

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INSERT INTO bad_urls(ID,DATA,ATTEMPTS,REASON) VALUES
(3376,'http://www.oit.itd.umich.edu/projects/adw2k/chordata/aves.html',0,'Unknown
Host')

java.sql.SQLException: results returned
at java.lang.Throwable.fillInStackTrace(Native Method)
at java.lang.Throwable.fillInStackTrace(Compiled Code)
at java.lang.Throwable.<init>(Compiled Code)
at java.lang.Exception.<init>(Compiled Code)
at java.sql.SQLException.<init>(SQLException.java:82)
at postgresql.Statement.executeUpdate(Compiled Code)
at postgresql.PreparedStatement.executeUpdate(Compiled Code)
at InsertError.record(Compiled Code)
at InsertError.record(Compiled Code)
at wbCheckUrl$CheckThread.run(Compiled Code)