Okay, found it.
It seems FF doesn't send the value of an image input, whereas Chrome does:
<input type="image" name="open" value="1"
$_POST['open'] is 1 in Chrome and NULL in Firefox.
Fixed it now by using another hidden var.
Are you the owner of bitcoinbalance.com?? I need to ask you something.
Yep, how can I help?
I am working on a site that you pick a number from 1-3 and if you win you win back double your bet. I wanted to know if I could use your site for people to deposit and withdraw
Thanks for the interest... I haven't completed the code yet to allow 3rd-party sites as that will be a bit more complex, security-wise.
The reason I'm able to connect my sites easily at present is because they all directly hook in to the same database and are hosted on the same server.
What other options are you considering for registration/payments? (using mybitcoin or running bitcoind yourself?)