diff --git a/contracts/DelayedClaimable.sol b/contracts/DelayedClaimable.sol
index 08b3b94a5..5e97e82cf 100644
--- a/contracts/DelayedClaimable.sol
+++ b/contracts/DelayedClaimable.sol
@@ -10,13 +10,16 @@ import './Claimable.sol';
 contract DelayedClaimable is Ownable, Claimable {
   uint public claimBefore;
 
+  modifier onTime() { 
+    if (block.number < claimBefore)
+      _;
+  }
+
   function setDelay(uint _claimBefore) onlyOwner {
     claimBefore = _claimBefore;
   }
 
-  function claimOwnership() onlyPendingOwner {
-    if (block.number > claimBefore)
-        throw;
+  function claimOwnership() onlyPendingOwner onTime {
     owner = pendingOwner;
     pendingOwner = 0x0;
     claimBefore = 0;
diff --git a/test/DelayedClaimble.js b/test/DelayedClaimble.js
index 61c4a5e77..7c0a4c581 100644
--- a/test/DelayedClaimble.js
+++ b/test/DelayedClaimble.js
@@ -22,7 +22,9 @@ contract('DelayedClaimable', function(accounts) {
       })
       .then(function(pendingOwner) {
         assert.isTrue(pendingOwner === newOwner);
-        delayedClaimable.claimOwnership({from: newOwner});
+        return delayedClaimable.claimOwnership({from: newOwner});
+      })
+      .then(function() {
         return delayedClaimable.owner();
       })
       .then(function(owner) {
@@ -46,7 +48,9 @@ contract('DelayedClaimable', function(accounts) {
       })
       .then(function(pendingOwner) {
         assert.isTrue(pendingOwner === newOwner);
-        // delayedClaimable.claimOwnership({from: newOwner}); Uncomment to break the test.
+        return delayedClaimable.claimOwnership({from: newOwner});
+      })
+      .then(function() {
         return delayedClaimable.owner();
       })
       .then(function(owner) {