Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/NodeTypeInstanceHandler.java
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/NodeTypeInstanceHandler.java	(revision 808353)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/NodeTypeInstanceHandler.java	(working copy)
@@ -104,6 +104,12 @@
             if (NameConstants.MIX_LASTMODIFIED.equals(declaringNT)) {
                 genValues = new InternalValue[]{InternalValue.create(userId)};
             }
+        } else if (NameConstants.JCR_ETAG.equals(name)) {
+            // jcr:etag property of a mix:etag
+            if (NameConstants.MIX_ETAG.equals(declaringNT)) {
+                // TODO: provide real implementation
+                genValues = new InternalValue[]{InternalValue.create("")};
+            }
         }
         return genValues;
     }
Index: jackrabbit-core/src/main/resources/org/apache/jackrabbit/core/nodetype/builtin_nodetypes.cnd
===================================================================
--- jackrabbit-core/src/main/resources/org/apache/jackrabbit/core/nodetype/builtin_nodetypes.cnd	(revision 808353)
+++ jackrabbit-core/src/main/resources/org/apache/jackrabbit/core/nodetype/builtin_nodetypes.cnd	(working copy)
@@ -242,8 +242,7 @@
  */
 [mix:etag]
   mixin
-  // currently has a default value because auto-creation not handled see JCR-2116
-  - jcr:etag (STRING) = '' protected autocreated
+  - jcr:etag (STRING) protected autocreated
 
 //------------------------------------------------------------------------------
 // U N S T R U C T U R E D   C O N T E N T
Index: jackrabbit-jcr-tests/src/main/resources/org/apache/jackrabbit/test/api/nodetype/spec/mix-etag.txt
===================================================================
--- jackrabbit-jcr-tests/src/main/resources/org/apache/jackrabbit/test/api/nodetype/spec/mix-etag.txt	(revision 808353)
+++ jackrabbit-jcr-tests/src/main/resources/org/apache/jackrabbit/test/api/nodetype/spec/mix-etag.txt	(working copy)
@@ -11,7 +11,7 @@
 PropertyDefinition
   Name jcr:etag
   RequiredType STRING
-  DefaultValues []
+  DefaultValues null
   AutoCreated true
   Mandatory false
   OnParentVersion COPY