I had a quick look into the code and it seems to be more a limitation of the format rather than the platform.

When writing the content to an INI file, the code checks for QStringList or QVariantList and serializes that into a list.
Anything else is serialized as a string.

So the stream operators are not used at all.

You could try to register a converter (QMetaType::registerConverter) that serializes the list into a string.
Not sure if the same trick works the other way around though.

Cheers,
_