What I don't understand--and please bear with my naivety about Eclipse plugin development--is why we can't offer some sort of "smart" editor that is aware of the properties defined in the pom.xml file and can resolve them when it needs a value (such as the JTA data source name).

That is what I would like to do where we can - but will only work for our editors and projects. We don't control all of the IDE - sorry ;)
Anyway, the editor is just *one* part of this - then there is the whole set of framework specific models in place, i.e. JSF and JPA provided by WTP has their own little model which
expects things to be in a specific place and is not in any way extendable in this area (afaik).

btw. jta datasource name is an example of something we don't really need to resolve since it only exists at runtime....
what we want to control is that when you want to do Hibernate queries from the IDE you use a persistence.xml that is configured to run in J2SE;
but when deploying it should use the datasource name one - and this is not controllable with a mere property replacement because of how persistence.xml's are structured.

We'll need to discuss this in real time to make sound progress, likely JBossWorld. But I'll leave one statement/inquiry here.

So you are saying that Eclipse basically has no native support for property substitutions of any kind in project files? I just don't see how the Eclipse developers missed this absolutely critical requirement for an IDE. For as long as anyone has been developing Java EE web applications, system administrators have been using all sorts of voodoo magic property replacement to get any deployable build artifact. Variations are just a huge fact of life. The IDE has to be able to deal with that reality and stop living in it's own ideal world that every value in a file is concrete.

Putting my problem solving hat back on, the best way I have found to deal with this situation, from many years of having to get the IDE to operate in the real world, is to have an environment switcher. It tears through the project and replaces configuration files intended for one app server with configuration files for another. Then, you can edit them...but of course when you are all done tweaking them (with permanent changes), you have to copy the files back to their source to check them in. Otherwise, the changes are just temporary for your immediate development needs.

Am I missing some obvious way to work? Put Maven completely aside for a moment and just focus on how to deal with different settings for different environment in any Java EE project. How is the problem solved? That is where we need to start when we discuss a solution.

-Dan