Description:
------------
on firebird/interbase table.
pdo fetch data .
lost the first row data when the field type is blob.
php 5.11/5.12 too

Reproduce code:
---------------
//sql code
CREATE TABLE test (
    ID   INTEGER,
    DAT  BLOB SUB_TYPE 1 SEGMENT SIZE 80
);
//inset any data
INSERT INTO test (ID,DAT) VALUES (1,'aaa');
INSERT INTO test (ID,DAT) VALUES (2,'bbb');
//php code
$dbh = new PDO("firebird:dbname=xxx",'SYSDBA','masterkey');
$sth=$dbh->query('SELECT * from test;');
while ($row=$sth->fetch(2)){
       print_r($row);
}
//lost the first row data VALUES (1,'aaa')
Array
(
    [ID] => 
    [DAT] => 
)
Array
(
    [ID] => 2
    [DAT] => bbb
)