ODBC/SQL Server select bug

Weird error SELECTing from SQL Server 2005 via ODBC, which shows under the following
conditions:

* select contains 'left outer join' to a secondary table
* select contains an 'order by' clause
* the DBI->connect statement contains the option: 'odbc_SQL_ROWSET_SIZE' => 2

If the join doesn't match a row in the secondary table,  *all* values return are NULL, even the 
values in the primary table, as in rows 2 and 3 below:
--
5 rows 
1 )  plant=yellow coneflower fk=3
2 )  plant= fk=ERROR - not defined 
3 )  plant= fk=ERROR - not defined 
4 )  plant=elm-leafed goldenrod fk=3
5 )  plant=bottle gentian fk=5
--

If I comment out the join, or the order by, or the connect attribute, 
or if I change the connect attribute value to '1',  I get the expected  result:
--
5 rows 
1 )  plant=yellow coneflower fk=3
2 )  plant=obediant plant fk=100
3 )  plant=purple coneflower fk=
4 )  plant=elm-leafed goldenrod fk=3
5 )  plant=bottle gentian fk=5
---


FYI, I need the ROWSET option, because my application uses nested cursors.
Example code is show below. 
I have run this successfully on SQL Server 2000, so I suspect that some option
related to SS 2005 may be the issue. Any clues would be appreciated.

System:
OS: Win2003 server
DB: SQL Server 2005, Developer edition 
Perl: v 5.8.8, ActiveState
Modules: DBI  1.52, DBD::ODBC v1.22

Code:

use DBI;
print "connecting...\n";
my($dsn, $dbh, $db_user, $db_pwd);
$dsn = 'dbi:ODBC:plants';
$dbh = DBI->connect($dsn, $db_user, $db_pwd,
  {'odbc_SQL_ROWSET_SIZE' => 2 }  )
  || die("dbi connection failed: dsn=$dsn \n");
print "check: dbh=$dbh, err=" . $DBI::errstr . "\n";

$query = qq{ select plant.name as plant, plant.color_id
	from plant
	left outer join  color on plant.color_id = color.color_id
	order by plant.plant_id
	};

$dbh->{TraceLevel} = 15;
	
$sth = $dbh->prepare( $query );
$sth->execute( );
$rows = $sth->fetchall_arrayref();
print int(@$rows) . " rows \n";

$n=0;
foreach ( @$rows ) {
  $n++;
  print "$n ) ";
  print ' plant=' . $_->[0] . " fk=" . $_->[1] ;

  if ( ! defined $_->[0] ) {
	print "ERROR - not defined ";
  }
  elsif ( ! $_->[0] ) {
	print "ERROR - no value ";
  }
  print "\n";

}


Darin Burleigh
Software Engineer
CDW LLC.