FYI:
Using the IE8 beta2 that was released earlier this week, mail manager won't open properly. Appears to be due to the stricter security model of the browser not allowing authentication data to be passed between tabs or windows.
The powers that be at Astaro may want to begin playing around with this now, so that a fix or workaround can be put in-place before final release of the browser, which is expected to be in November.
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