400 Error when using "Back" button

[holmes-ra]

When using the Back button in the IGB after a POST submission (usually; sometimes it's seems to be random) you are presented with:

Error loading requested URL
Error Code: -400

Here's what is displayed in the EVE LogServer:

9 2011.06.03 01:22:10:404 ScatterEvent( OnWindowStopBlinking )
10 2011.06.03 01:22:10:519 [0602/212210:INFO:BrowserViewHost.cpp(227)] BrowserViewHost::SetSize: 826,546
11 2011.06.03 01:22:10:519 ScatterEvent( OnWindowStopBlinking )
12 2011.06.03 01:22:10:537 [0602/212210:INFO:cookie_monster_sqlite.cpp(140)] Posting delayed commit task
13 2011.06.03 01:22:10:537 [0602/212210:INFO:webviewproxy.cpp(1094)] did fail loading, error: net | -400
14 2011.06.03 01:22:10:553 [0602/212210:WARNING:BrowserView.cpp(243)] onBlockLoading: -400
15 2011.06.03 01:22:10:553 [0602/212210:INFO:BrowserView.cpp(237)] onFinishLoading
16 2011.06.03 01:22:10:620 Loading was blocked, code -400
17 2011.06.03 01:22:10:627 [0602/212210:INFO:BrowserViewHost.cpp(515)] Reading Transport DIB, process handle: 00000B1C, Transport DIB id: 23, handle id: 000004A8
18 2011.06.03 01:22:10:663 [0602/212210:INFO:BrowserView.cpp(249)] onReceiveTitle: Error loading requested URL,
19 2011.06.03 01:22:10:663 [0602/212210:INFO:BrowserView.cpp(237)] onFinishLoading

I have no idea why this happens. When using Firefox 4 (modify headers to gain access), there is no error. Perhaps someone out there will know. Note sure if it's a problem with the IGB or with the code. It doesn't seem to be a detrimental bug in that any ill-effects can come from it (double submission of forms, etc) -- all it seems to do is error out.