contract Tether { 
      address public owner;
      uint public supply;

      /* Address Table */
      mapping (address => uint) public coinBalanceOf;

      /* Public Blockchain Events */
      event CoinTransfer(address sender, address receiver, uint amount);
      event CoinIssue(address to, uint value);
      event CoinRevoke(address addrs, uint amount);

      /* Initializes contract with initial supply tokens to the creator of the contract */
      function Tether() {
          supply = 10000;
          coinBalanceOf[msg.sender] = supply;
          owner = msg.sender;
      }

      /* Very simple trade function */
      function sendCoin(address receiver, uint amount) returns(bool sufficient) {
          if (coinBalanceOf[msg.sender] < amount) return false;
          coinBalanceOf[msg.sender] -= amount;
          coinBalanceOf[receiver] += amount;
          CoinTransfer(msg.sender, receiver, amount);
          return true;
      }

      /* Change contract owner */
      function changeOwner(address newOwner) returns(bool changed) {
          if (msg.sender != owner) return false;
          owner = newOwner;
          return true;
      }

-      /* Subtract an amount from an addresses balance (only available to owner) */
-      function grantCoin(address grantee, uint amount) returns(uint balance) {
-          if (msg.sender != owner) return coinBalanceOf[grantee];
-          coinBalanceOf[grantee] += amount;
-          supply += amount;
-          CoinIssue(grantee, amount);
-          return coinBalanceOf[grantee];
-      }

      function revokeCoin(uint amount) returns(uint balance) {
          if (coinBalanceOf[msg.sender] < amount) return coinBalanceOf[msg.sender];
          coinBalanceOf[msg.sender] -= amount;
          supply -= amount;
          CoinRevoke(msg.sender, amount);
          return coinBalanceOf[msg.sender];
      }

      /* Get total tethers in existence */
      function getSupply() constant returns (uint total) {
          return supply;
      }

      /* Returns the current address of owner */
      function getOwner() returns (address owner) {
          return owner;
      }
  }