In r1146847, I committed a change to use system property interpoliation on the sling.home servlet context parameter. To do so, I copied the substVars static method from org.apache.sling.launchpad.base.impl.Sling into org.apache.sling.launchpad.webapp.SlingServlet. Although I hate to copy code, as far as I know, we can't have a dependency between these two classes and it seems too heavyweight to extract this single method into some common utility project.
WDYT? Justin
