It is possible for one property to reference another property.
A property value may be a reference to another property, which saves having multiple copies of the same regular expression. This is indicated by a $ as the first character of the property value. If the first character of an expression needs to be a $ it too may be escaped with a \. An example of this is shown below:
audit.filter.alfresco-access.transaction.type=$transaction.content.types transaction.content.types=$general.content.types general.content.types=cm:folder;cm:content