Ethereum classic has decided to diverge from Ethereum on the go implementation. They have just made a new release that is incompatible to current ETH geth.
Ethcore has implemented this "divergence" into their codebase so parity remains a compatible client for both ETH and ETC.
All ETC users of Etherwall will need to supply their own geth unless the original geth incorporates these changes.
Since I do not officially support ETC with my releases I will continue to supply the ETH geth with Etherwall until version 2 with dual node support and automated client downloads.
Aleš Katona is an open source contributor and author of various projects like Etherwall and Lighthouse.