Description:
------------
It looks like the extension doesn't implement any special handling of the PDO::PARAM_BOOL binding type which makes the logic of binding boolean values inconsistent with the rest of the PDO extensions.

Test script:
---------------
$conn = new PDO('oci:dbname=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521))(CONNECT_DATA=(SID=XE)))', 'system', 'oracle');
$stmt = $conn->prepare('SELECT ?, ? FROM DUAL');
$stmt->bindValue(1, true, PDO::PARAM_BOOL);
$stmt->bindValue(2, false, PDO::PARAM_BOOL);
$stmt->execute();


Expected result:
----------------
array(2) {
  [0] =>
  string(1) "1"
  [1] =>
  string(1) "0"
}


Actual result:
--------------
array(2) {
  [0] =>
  string(1) "1"
  [1] =>
  NULL
}