A companion project
so5extra has been updated to v.1.3.1.
There is just one small feature in the new version of so5extra: broadcasting mbox. That mbox resend a message to every mbox from a predefined set of destination mboxes. For example, you can have some worker agents that wait for a message from their direct mboxes. You can add their direct mboxes to a new broadcasting mbox and then send just one message. That message will be delivered to all worker agents.
More information about this new type of mbox can be found
here.
Note. so5extra-1.3.1 implements broadcasting mbox with a fixed set of destinations. If you want to have a mbox with a set of destination that can be modified after the creation of a mbox instance then open an issue on BitBucket or GitHub.