diff --git a/build.gradle b/build.gradle
index df6eeb6..f9298c4 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1033,5 +1033,5 @@
 //  2) /gradlew.bat which is the windows bat script for for executing builds
 //  3) /gradle/wrapper which is a directory named by the "jarPath" config which contains other needed files.
 task wrapper( type: Wrapper ) {
-  gradleVersion = '2.5'
+  gradleVersion = '2.11'
 }
diff --git a/core/testsupport/src/main/java/org/apache/zest/test/indexing/model/Address.java b/core/testsupport/src/main/java/org/apache/zest/test/indexing/model/Address.java
old mode 100644
new mode 100755
index 1d5c03a..60aa742
--- a/core/testsupport/src/main/java/org/apache/zest/test/indexing/model/Address.java
+++ b/core/testsupport/src/main/java/org/apache/zest/test/indexing/model/Address.java
@@ -20,7 +20,7 @@
 import org.apache.zest.api.property.Property;
 import org.apache.zest.api.value.ValueComposite;
 
-public interface Address
+public interface Address extends ValueComposite // necessary, @See ZEST-137
 {
     Property<String> line1();
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 48f202a..fafa8dd 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.5-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-2.11-bin.zip