Unable to delete cart price rule in version 1.8.1

[Epo123]

We've recently upgraded the module to version 1.8.1 from 1.7.4 and we've noticed that since this version the module is inputting values in the table 'mp_catalog_rule_updated_at' and since in the UpgradeSchema you are creating a foreign key relation for which you have not set the 'onDelete' action for this, when trying to delete a cart price rule you get an error saying you cannot delete the rule.
The error generated is as follows (xdebug):
SQLSTATE[23000]: Integrity constraint violation: 1451 Cannot delete or update a parent row: a foreign key constraint fails (magento.mp_catalog_rule_updated_at, CONSTRAINT catalogrule FOREIGN KEY (catalog_rule_id) REFERENCES catalogrule (rule_id)), query was: DELETE FROM catalogrule WHERE (rule_id = '1')

Please look into this and resolve the issue in a next version.

[marcoboom]

This is still an issue. Is anyone working on this issue?