Inline multicast activate only activates the first target

Question

++ and --++ don't work as expected in multicasts; only the first target gets activated.

Currently this code only results in Bob being activated, not Dave or Charlie:

@startuml
!pragma teoz true
actor Alice
actor Bob
actor Charlie
actor Dave
Bob -> Alice ++: message1
Alice -> Bob & Dave & Charlie --++: multicast message
@enduml

http://www.plantuml.com/plantuml/uml/DOux3W8n34Hxdy8qswnIq5AWvNEH8LXBf8GWnw7Wz8GDwKRpdgrPYa6jfaYxbs9DO9FyOTCg16zP-HI37_cSR_zqUK1Z6FqLRw46sHsxp_Dyu2IbO9KzzQgndp9jDa_Z1JktoJLQy2WspcYHvxqD-m80

Note you can work around this by activating Charlie and Dave manually after the multicast:

Alice -> Bob & Dave & Charlie --++: multicast message
activate Charlie
activate Dave