$DDI = 1;
$CPIN = 0;
$MPIN = 0;
$Info = " ";
$ResRef = 0;
$ConfRef = 0;
$ActDuration = 0;
$AvailInd = 0;
$rc = 0;
$dbh->do('use BSRes2');
$sth = $dbh->prepare('
       declare @DDI UDTDDI, @CPIN UDTPIN, @MPIN UDTPIN, @Information UDTComment, 
@ReservationRef int, @ConferenceRef int, @ActualDuration int, @AvailableInd UDTFlag
       select @DDI = ?, @CPIN = ?, @MPIN = ?, @Information = ?, @ReservationRef = ?, 
@ConferenceRef = ?, @ActualDuration = ?, @AvailableInd = ?
       execute p_ccs_MakeBooking @ClientAccount="xxxxxx", [...] @DDI=@DDI OUTPUT, 
@CPIN=@CPIN OUTPUT, @MPIN=@MPIN OUTPUT, @Information=@Information OUTPUT, 
@ReservationRef=@ReservationRef OUTPUT, @ConferenceRef=@ConferenceRef OUTPUT, 
@ActualDuration=@ActualDuration OUTPUT, @AvailableInd=@AvailableInd OUTPUT');

$sth->bind_param_inout(1, \$DDI, 32, DBI::SQL_VARCHAR);
$sth->bind_param_inout(2, \$CPIN, 12, DBI::SQL_VARCHAR);
$sth->bind_param_inout(3, \$MPIN, 12, DBI::SQL_VARCHAR);
$sth->bind_param_inout(4, \$Info, 255, DBI::SQL_VARCHAR);
$sth->bind_param_inout(5, \$ResRef, 10, DBI::SQL_INTEGER);
$sth->bind_param_inout(6, \$ConfRef, 10, DBI::SQL_INTEGER);
$sth->bind_param_inout(7, \$ActDuration, 10, DBI::SQL_INTEGER);
$sth->bind_param_inout(8, \$AvailInd, 1, DBI::SQL_BIT);
$sth->execute();