[BUG] Lombok in Intellij fails with Eclipse compiler and custom ECJ

[blacelle]

Context
For some reason, IntelliJ is slow to start unit-tests, on the "Parsing java" step. So I tried switching to Eclipse compiler.

Though, default ECJ is not compatible with JDK21 (https://youtrack.jetbrains.com/issue/IDEA-355457/Update-Eclipse-ECJ-compiler), so I relied on a ECJ jar downloaded manually (Intellij embed an (old?) ECJ): https://archive.eclipse.org/eclipse/downloads/drops4/R-4.34-202411201800/

On re-building my project, I now see the bug.

Describe the bug
When compiling my project in IntelliJ, I see:

Executing pre-compile tasks…
Running 'before' tasks
Checking sources
Copying resources… [adhoc]
Dependency analysis found 0 affected files
Updating dependency information… [adhoc]
Parsing java… [adhoc]
java: You aren't using a compiler supported by lombok, so lombok will not work and has been disabled.
Your processor is: org.jetbrains.jps.javac.$Proxy16
Lombok supports: OpenJDK javac, ECJ

To Reproduce

• Start Intellij
• Install Lombok Plugin
• Switch to Eclipse compiler, and provide a custom ECJ
• Build

Expected behavior
Build including Lombok processing.

Version info (please complete the following information):

• Lombok version: 243.21565.193 as Intellij Lombok plugin version. I do not get how to check the actual Lombok version
• Intellij: Build #IC-243.21565.193, built on November 13, 2024
• ECJ 4.34

Additional context
Seem related (if not duplicate) of #2670