database error

Hi,

I installed this module to a postgres Drupal installation, and when I ran cron, I got an error message, which pointed out a database design error.

* warning: pg_query() [function.pg-query]: Query failed: ERROR: operator does not exist: character varying < integer LINE 2: WHERE timestamp < 1239802437 ^ HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts. in /.../includes/database.pgsql.inc on line 139.
* user warning: query: DELETE FROM services_timestamp_nonce WHERE timestamp < 1239802437 in /.../sites/all/modules/services/services.module on line 17.

The problem is that you shouldn't store this kind of data in a varchar field. Use datetime type instead. I attached a patch for the install file.