Dynamic Web Project isn't created properly when JBoss Portlet Tool installed

When I run the wizard for creating a "Dynamic Web Project" when JBoss Portlet Tool is installed and I hit "Finish" a project is created but the dialog doesn't disappear. When I then hit "Finish" a second time I get an error message stating:

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One or more constraints have not been satisfied.
Cannot install project facet Java 6.0. Some version of this project facet is already installed.
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When I then click "OK" the dialog disappears. Nevertheless the created project only contains a "src" and "build" folder. "WebContent" is missing.

I could reproduce this issue on several machines, each with a clean Eclipse (Galileo and/or Helios) and the latest stable release of JBoss Tools in the Galileo case and the latest development milestone in the Helios case.