CXF uses an old dependency that is not compatible with camel 4, undertow-servlet-jakarta.

By running the attached project with mvn spring-boot:run you can observe the failure ClassNotFoundException: jakarta.servlet.SingleThreadModel that is caused by the mismatch.

By commenting out the exclusion in the pom.xml and the undertow dependency, the project start and work as expected.

I think that we should have 2 objective regarding CXF:

1. Use undertow-servlet (same version as spring-boot and camel, 2.3.7.Final ATM) instead of undertow-servlet-jakarta which is an old and unused dependency, undertow migrated to jakarta on the main artifacts some time ago (High priority)
2. Update to jakarta 10, in particular, cxf.servlet-api.version=6.0.0 (lower priority, maybe not mandatory since our integration tests are successful with the bullet point)