PHP5RC2 and PEAR DB Problem

With PHP5RC2, DB::connect() is not returning the correct type of object.

#!/usr/local/bin/php
<?php
require_once("DB.php");

$dsn = "odbc://db2inst1:badpasswd@testdb";
$db = DB::connect($dsn);
echo $db->getMessage();
if(DB::isError($db))
echo "Connect failed!";
else
{
$res = $db->query("SELECT * FROM test_tbl");
while($row = $res->fetchRow())
echo $row[0] . "\n";
$db->disconnect();
}
?>

The password in the DSN is wrong and DB2 reports the error, however
DB::connect() still returns an object of type DB_odbc. I've traced
connect() in DB/odbc.php and confirmed that it recognized that
odbc_connect() failed and goes into that code path and creates a DB_error
object and I've even printed out the type of the object inside the function
before it returns it, but in the caller (my test script above), the reported
type is DB_odbc and so the if statement is false and then it tried to run
the query, but then I get a series of odbc_*() errors because there's no
valid resource for those functions to operate on. Has anyone been able to
use PEAR DB, specifically the ODBC driver, with PHP5RC2? The code above
works on another system, as expected, with PHP 4.3.6.

Thanks,

Derek