Looking at the DS codebase there are few notes which indicate that this is not portable e.g:

• ConfigurationExtension
• PropertyFileConfig

Finally Java EE spec clearly states in EE.8.3 Class Loading Requirements:

Portable applications must not depend on the types of class loaders used or the hierarchical arrangement of class loaders, if any.

which is exactly what happens in ConfigurationExtension.addParentPropertyFileConfigs