Configuring "org.ops4j.pax.logging" properties through JMX causing property placeholders to be replaced

Issue

When configuring "org.ops4j.pax.logging" PID properties through JMX setProperty operation on Hawtio JMX Page:

org.apache.karaf:type=config,name=root::setProperty(java.lang.String,java.lang.String,java.lang.String)

any property with property placeholders gets replaced automatically. For instance, the following two properties:

log4j.appender.out.file=${karaf.data}/log/fuse.log
log4j.appender.sift.appender.file=${karaf.data}/log/$\\{bundle.name\\}.log

After invoking setProperty JMX operations twice, above properties are changed to:

log4j.appender.out.file = /apps/jboss/fuse/6.3/r8/orig/jboss-fuse-6.3.0.redhat-347/data/log/fuse.log
log4j.appender.sift.appender.file = /apps/jboss/fuse/6.3/r8/orig/jboss-fuse-6.3.0.redhat-347/data/log/.log