fixed DoS hole - noted Unlimited coins possible

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Hash: SHA1

USDE:

I fixed dos hole

your code allows unlimited coins! There is no cap!

please discuss if you wish a fix.
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Version: BCPG v1.47

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dGNodW1AdmlzdG9tYWlsLmNvbT4ACgkQu8Tc5rjr4IkmIACaAhiE5/Z0gwZDG686
XH2Lku5bU3IAnjScBqeqLqLFFkZzeMtWEzk3o102
=E9mm
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