diff --git a/classes/query_builder.php b/classes/query_builder.php
index 0ab4a7f..5e006f6 100644
--- a/classes/query_builder.php
+++ b/classes/query_builder.php
@@ -116,7 +116,7 @@ class Query_Builder {
 	 *
 	 * @var DB_PDO
 	 */
-	private $sql;
+	public $sql;
 
 	/** 
 	 * Query component order mapping
diff --git a/drivers/firebird/firebird_sql.php b/drivers/firebird/firebird_sql.php
index 97f43e3..5535884 100644
--- a/drivers/firebird/firebird_sql.php
+++ b/drivers/firebird/firebird_sql.php
@@ -248,7 +248,9 @@ SQL;
 	public function type_list()
 	{
 		return <<<SQL
-			SELECT "RDB\$FIELD_TYPE" FROM "RDB\$FIELDS"
+			SELECT "RDB\$TYPE_NAME", "RDB\$FIELD_NAME" FROM "RDB\$TYPES"
+			WHERE "RDB\$FIELD_NAME" IN ('RDB\$FIELD_TYPE', 'RDB\$FIELD_SUB_TYPE')
+			ORDER BY "RDB\$FIELD_NAME" DESC, "RDB\$TYPE_NAME" ASC
 SQL;
 	}
 
diff --git a/drivers/pgsql/pgsql_sql.php b/drivers/pgsql/pgsql_sql.php
index ac97752..2293dcb 100644
--- a/drivers/pgsql/pgsql_sql.php
+++ b/drivers/pgsql/pgsql_sql.php
@@ -222,7 +222,7 @@ SQL;
 		return <<<SQL
 			SELECT "typname" FROM "pg_catalog"."pg_type"
 			WHERE "typname" !~ '^pg_|_'
-			AND "typtype" != 'c'
+			AND "typtype" = 'b'
 			ORDER BY "typname"
 SQL;
 	}
diff --git a/tests/databases/firebird/firebird-qb.php b/tests/databases/firebird/firebird-qb.php
index a3b01f1..a202ab0 100644
--- a/tests/databases/firebird/firebird-qb.php
+++ b/tests/databases/firebird/firebird-qb.php
@@ -35,4 +35,16 @@ class FirebirdQBTest extends QBTest {
 		
 		// echo '<hr /> Firebird Queries <hr />';
 	}
+	
+	public function TestTypeList()
+	{
+		$sql = $this->db->sql->type_list();
+		$query = $this->db->query($sql);
+		
+		$this->assertIsA($query, 'PDOStatement');
+		
+		$res = $query->fetchAll(PDO::FETCH_ASSOC);
+		
+		$this->assertTrue(is_array($res));
+	}
 }
\ No newline at end of file
diff --git a/tests/db_files/FB_TEST_DB.FDB b/tests/db_files/FB_TEST_DB.FDB
index b3b7c90..2953a58 100644
Binary files a/tests/db_files/FB_TEST_DB.FDB and b/tests/db_files/FB_TEST_DB.FDB differ