Testing webapp in slow network

I don't know if this is the kind of question I 开发者_StackOverflow社区can ask here, but here I go.

I have a ajax packed web application and some bugs show up only on slow networks (atleast probability of those bugs are higher in such an environment). So my question is this -- is these some tool which will help to simulate a slow network for testing purposes.

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Delay some time on server-side.

You haven't told anything about your code, but it can be: started another request while previous one is in progress (not processed yet, not returned yet), timeout returned false data.