Intellij 9 artifacts "forgetting" libraries

Has anybody else had issues where Intellij 9 "forgets" what libraries you added to an artifact configuration? I am using maven modules within Intel开发者_如何学Clij 9.0.2 which seem to auto add my libraries to my artifact however both my hibernate-core jar and the "GWT compiler output" keep disappearing from the artifact config.

What is even worse is that when I do a rebuilt Intellij seems to ignore the fact that I made these changes if I do not "invalidate caches".

Any ideas or similar experiences?

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Do you have 'hibernate-core' library and gwt-plugin configured in your pom.xml or you've added it by hand in IDEA settings? Could you please create an issue in IDEA bug tracker (http://youtrack.jetbrains.net/issues/IDEA) and attach your pom.xml to it?

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The problem was that I had my hibernate-core lib added as follows...

        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>3.5.1-Final</version>
            <optional>true</optional>
        </dependency>

By removing the optional parameter Intellij added this to my artifact and it stays.