select_or_other_content_allowed_values_alter() prevents deleting a node

In issue #1013716: key|value pairs not working on display the select_or_other_content_allowed_values_alter() was introduced. (Probably added in 6.x-2.4.) This function populates the allowed values of CCK's Text widget using the options from the Select Or Other widget. It does it only when $_POST['op'] is not t('Save'). This effectively prevents deleting a node with validation error %name: illegal value. because in that case this condition is true. It is also true when renaming the Save button's value (using the Module Node Form Settings for instance).

Quick fix would be to add $_POST['op'] != t('Delete') to the condition. That will not help though if the buttons value(s) is renamed to something other.