Spending unconfirmed outputs in the presence of malleable transactions is unsafe. The reference client allows spending unconfirmed change outputs as they used to be considered safe. But if the original transactions is modified then the chain of unconfirmed transactions becomes double spent and the reference client gets confused about balances.
Spending unconfirmed outputs in the presence of malleable transactions is unsafe. The reference client allows spending unconfirmed change outputs as they used to be considered safe. But if the original transactions is modified then the chain of unconfirmed transactions becomes double spent and the reference client gets confused about balances.