Is Project Facets part of Vaadin development environments? I have a project facet for my development environment that says Java 1.6, Dynamic Web Page 3.0. When I change Java to 1.5 it says that DWP 3.0 needs Java 1.6. When I change DWP to 2.5 (the next lowest) it says that I can’t do that.
If this facet isn’t part of development I’ll try creating my own.
The Vaadin core project is normally developed as a Dynamic Web Project in Eclipse - not strictly necessary but makes some things easier.
You should choose version 2.4 (or 2.5) of the Dynamic Web Page (or whatever Eclipse calls it) facet, though - it matches the supported application server environments and supports Java 1.5.
Unfortunately, that facet in Eclipse WTP does not support downgrading once a certain version has been added to a project - you either need to recreate the Eclipse project files or edit them by hand to remove/modify the facet (you can try to edit .settings/org.eclipse.wst.common.project.facet.core.xml by hand - not sure if that is enough).