Until https://bugs.freedesktop.org/show_bug.cgi?id=13348 is fixed, perhaps Gabble should use the current global alias, rather than the username part of the global JID, as the nickname in a MUC. After #13348 is fixed, it could perhaps still use the global alias as the default.
Fixed in HEAD now, should be included in Gabble 0.7.7.
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