Tmux hampers osascripts display notification

I like to show notifications from scripts using osascript -e 'display notification "Some text"'.

This works fine from the plain shell but it stop working when in tmux.

It just doesn't show the notification in tmux. No errors or anything else is shown.

Has anyone else had this problem and how do I fix it?

I don't plan to use Tmux but just from curiosity I leafed through its manual pages and saw under "Options":

focus-events [on|off]
When enabled, focus events are requested from the terminal if supported
and passed through to applications running in tmux. Attached clients 
should be detached and attached again after changing this option.

You might look into Tux' options to get what you want, I guess.