Login issues when used with authentication modules.

Please see:

http://drupal.org/node/1552326

We see same problem while using signature_forums with shib_auth module (http://drupal.org/project/shib_auth): when new user comes to the site for first time and his/hers account is being created by shib_auth/drupal it ends up with the error:

PDOException: SQLSTATE[HY000]: General error: 1364 Field 'signature' doesn't have a default value: INSERT INTO {users} (uid, name, pass, created, access, status, init) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6); Array#012(#012    [:db_insert_placeholder_0] => 143#012    [:db_insert_placeholder_1] => XXXXXX#012    [:db_insert_placeholder_2] => XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX#012    [:db_insert_placeholder_3] => XXXXXXX#012    [:db_insert_placeholder_4] => 1347262287#012    [:db_insert_placeholder_5] => 1#012    [:db_insert_placeholder_6] => XXXXXXX#012)#012 in drupal_write_record() (line 7013 of /XXXXX/drupal/includes/common.inc).

The offending code is:

unset($schema['users']['fields']['signature']['default']);

at line 50 of signature_forum.install which will set 'users' table 'signature' column default value to NULL while drupal 7 DB schema specifies this column as 'NOT NULL' without default value...

Jarek