Please see the attached images ran using the 7u4 - b225 and the default JDK 6 builds

JDK6 has white background

JDK7u4 version has a grey background. Tried the 7u4 on a windows system, this has a White background. So there is a regression in the background color.

I believe Policy Tool is very old written using awt, may be this bug needs to be moved to awt from swing.