Optional empty raw IP Address Field causes SQL error SQLSTATE[23000]: Integrity constraint violation - field cannot be null

Steps to replicate:
Install module as normal
Create a 'range' (not 'raw' as in title - oops) Ip address field. Leave as optional (as opposed to 'required')
Attempt to add a node and leave the IP address field blank

If I am correct you will receive an error as follows:
DOException: SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'field_device_external_ip_start' cannot be null: INSERT INTO {field_data_field_device_external_ip} (entity_type, entity_id, revision_id, bundle, delta, language, field_device_external_ip_start, field_device_external_ip_end) 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, :db_insert_placeholder_7); Array ( [:db_insert_placeholder_0] => node [:db_insert_placeholder_1] => 243 [:db_insert_placeholder_2] => 245 [:db_insert_placeholder_3] => device_node [:db_insert_placeholder_4] => 0 [:db_insert_placeholder_5] => und [:db_insert_placeholder_6] => [:db_insert_placeholder_7] => ) in field_sql_storage_field_storage_write() (line 424 of
\modules\field\modules\field_sql_storage\field_sql_storage.module).

May try and upgrade to latest dev version (once I work out how to upgrade a field module with dependent fields in content types)

Regards

Adam