problem with querying snmpv3 with auth and priv

I am using the Net::SNMP module for polling and am tring to use the
authkey and privkey feature to prevent having passwords in the
script. I can poll my agent with the following command:

# snmpwalk -a md5 -l authpriv -v3 -u test1 10.140.186.65 -x DES -X
password -A password 1.3.6.1.2.1.2.1.0
IF-MIB::ifNumber.0 = INTEGER: 57

I generated keys using snmpkey:

secengdev07:/home/firesu # snmpkey md5 password
0x800007E580723A9134B3EBC945 des password
authKey: 0x2304444b34a3cab354361d9a92f69a14
privKey: 0x2304444b34a3cab354361d9a92f69a14

And I wrote the following test script:

#!/usr/bin/perl -w

use Net::SNMP;
use Data::Dumper;
use strict;


my $hostname = "10.140.186.65";
my $port = "161";
my $version = "3";
my $domain = "udp";
my $username = "test1";
my $authpasswd = "password";
my $privpasswd = "password";

my $authprotocol = "md5";
my $authkey = "0x2304444b34a3cab354361d9a92f69a14";

my $privprotocol = "des";
my $privkey = "0x2304444b34a3cab354361d9a92f69a14";

my $seconds = 2;
my $count = 3;

# requires a hostname and a community string as its arguments
my ($session, $error) = Net::SNMP->session(
-hostname => $hostname,
-port => $port,
-version => $version,
-domain => $domain,
-timeout => $seconds,
-retries => $count,
-username => $username,
-authprotocol => $authprotocol,
# -authpassword => $authpasswd,
# -privpassword => $privpasswd,
-authkey => $authkey,
-privprotocol => $privprotocol,
-privkey => $privkey
);

die "session error: $error" unless ($session);

# iso.org.dod.internet.mgmt.mib-2.interfaces.ifNumber.0 =
# 1.3.6.1.2.1.2.1.0
my $result = $session->get_request("1.3.6.1.2.1.2.1.0");

die "request error: ".$session->error unless (defined $result);

$session->close;

print Data::Dumper->Dump([$result]), " ", $error;

print "Number of interfaces: ".$result->{"1.3.6.1.2.1.2.1.0"}."\n";


If I use the passwords (rather than keys) then I can poll the agent.
However if I use the keys, then I see the following when running snmp
agent in debug:

Feb 8 11:27:35 cluster6-pfw snmpd[16447]: Parsed SNMPv3 message
(secName:test1, secLevel:authPriv): USM authentication failure
(incorrect password or key)

The agent version is:
[Expert@cluster6-pfw]# snmpd -v

NET-SNMP version: 5.0.9
Web: http://www.net-snmp.org/
Email: net-snmp-coders@lists.sourceforge.net

My question is, is my syntax correct for the snmpkey and perl script?
Should I contact the vendor of the snmp agent?

TIA for your time, Steve.