@s{quotedtext}
@s{quotedtext}
It is definitely an issue-- the account code doesn't keep track of where the coins it is sending out came from, so if you accept 0-confirmation coins you're vulnerable to double-spending attacks (see, for example, the discussion of the "Finney attack" in these forums).
Seeing coins show up right away is a fantastic feature, though, so I'd suggest getting the 0-confirmation balance and a 3+-confirmation balance, allowing only 3+ confirmed coins to be withdrawn, and displaying the difference as 'waiting confirmation'.