my $sth = $dbh->prepare( $query ) || die "Could not prepare" ;
foreach my $row ( @$class_arrayref )
{   
	( $bind_class ) = @$row;
	print "class = ".$bind_class."\n"; #debugging, works!
	$sth->bind_param( 1, $bind_class ); # does not work
}   
my $class = 'debian%';
$sth->bind_param( 1, $class ); # works!
$sth->execute;
my $rows = $sth->fetchall_arrayref();