please have a look
http://www.plantuml.com/plantuml/uml/POynheD034JhlwSOqT301Nx59TBHBBjEM8MrqTf9WxXxdAICvERDo4-QIIqsUzGjwBtm7bkigCAIrYQLqEX9JIc4Foks4VhVhaTHi9YpxfICCWh3LWBLXN9spjxc4cykTrDC9WtTHQbrY8eFU-uEmY9cKY7NR_oFuvXvPd_TLnYfmJbY774iGnhoEVFxpZ0HPv_n0W00
in the example above the embedded diagram should be reversed too
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