Intellij Idea does not display javac compiler warnings of referencing proprietary API

I'm w开发者_如何学Goorking with Intellij Idea 10 and Java 6 JDK Update 7. When I run Build --> Rebuild Project command, the javac compilation (using parameter -Xlint:all) displays warnings, but for some reason does not include warnings about the source code referencing Sun proprietary API classes.

When I run javac (yes, the same version that is referenced from Idea) manually from the command line, I can see those warnings all right. And I would like to see the same information in Idea as well. How do I achieve this?

It seems to be a bug. Could be that IDEA doesn't support some of the warning types and doesn't report them. Please submit an issue with the sample project attached.