Not directly - tho I done this in the past and have thought about turning it somehow into a command. But...
1) Start a new feature, call it your-epic
2) git branch -m feature/your-epic to stream/your-epic
3) git flow init - reconfigure git-flow to use stream/your-epic as the develop branch, use your-epic as the feature prefix
4) start/finish features as normal, git-flow merges features back into epic/your-epic
5) when finished, git flow init back to normal settings
6) git branch -m stream/your-epic back to feature/your-epic
7) git flow feature branch feature/your-epic
Automating this into some form of "git flow epic start/finish" would be good, but could be messy keeping track of all the different configuration pairs, should be doable tho.
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"Great artists are extremely selfish and arrogant things" — Steven Wilson, Porcupine Tree