MDB2_Schema : how to specify auto_increment ? (and other questions)

I try to use MDB2_Schema for alter, create and generate schema files. But there is no end user documentation so I try to ask my questions here. The dump operation succeed. I try with : 'portability' => (MDB2_PORTABILITY_ALL ^ MDB2_PORTABILITY_EMPTY_TO_NULL) and 'portability' => (MDB2_PORTABILITY_ALL ) But when I try to reload the xml file, I encounter several problems : - the fields with auto_increment property lost this property. How can I keep auto_increment property ? - In my database, I had 'not null' fields but no default value. The generated files describe : in the first case <field> <name>idh</name> <type>integer</type> </field> in the second case <field> <name>idh</name> <type>integer</type> <notnull>1</notnull> </field> In the first case I lost "not null" properties. In the second case I can't reload with MDB2_schema, the message is : [userinfo] => Parser error: if field is "notnull", it needs a default value - No error - Byte: 198; Line: 17; Col: 100 If I use : <default></default> (for empty) I get another errors : [userinfo] => [Last query: CREATE TABLE histo (idh INT DEFAULT NULL NOT NULL,dateCol DATETIME DEFAULT '0000-00-00 00:00:00',nom CHAR (50) DEFAULT NULL NOT NULL,type CHAR (1) DEFAULT 'D' NOT NULL,result CHAR (1) DEFAULT 'D' NOT NULL,perte INT DEFAULT 0 NOT NULL)] [Native code: 1067] [Native message: Valeur par défaut invalide pour 'idh'] You can note the DEFAULT NULL NOT NULL that cause the problem. In conclusion, I don't know how to generate a correct schema files. Any idea ?