If Oracle has applied for the trademark - can't they object?
It may work differently in the US and EU, but here in AU the trademarking authority follows this process:
- verify the mark or name is eligible for trademark
- do a quick search to make sure there isn't an existing trademark in the same category
- publish the trademark application
- allow time for 3rd party objections to be raised (usually a few months)
The trademark is only granted if no sustainable objections are raised. In this case, I would assume that the Hudson community has a legitimate and sustainable objection to the registering of the trademark due to their use of the term.
If the trademark has not yet been granted then there should be time to register an objection and hopefully avoid the need to rename the project