A request has been denied as a potential CSRF attack
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2012-03-24 14:59:02,248 ERROR [http-8080-14] [org.directwebremoting.dwrp.Batch] error A request has been denied as a potential CSRF attack. -- referer: http://confluence.com:8080/pages/editpage.action?pageId=123456 | url: /dwr/call/plaincall/HeartbeatAjax.startActivity.dwr | userName: anonymous
Because this is a client side problem, it's difficult to institute a server level change to affect all clients. This error is harmless and will go away over time, as clients will refresh their browsers from time to time. To force the issue, you could instruct all your users to shift-reload while on the edit page screen.