How to avoid hard-coded paths in features.xml ?

Issue

• Is it possible to have some type of path resolver in features.xml, not using maven repository.
• We have several environments running on windows and others on unix. I would like to create exactly ONE features.xml file for each of our projects. This file CANNOT contain hard-coded file paths (to third party jars).
• Please provide an example where the path (to third party jars) is EITHER:
  • injected as a property.
  • relative to the container.
  • is defined in org.apache.karaf.features.cfg.