diff --git a/lib/pom.xml b/lib/pom.xml
index 8a32d50..1ae0a80 100644
--- a/lib/pom.xml
+++ b/lib/pom.xml
@@ -132,22 +132,15 @@
             <version>4.12</version>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <!-- Pull in asm-util and etc for tests and ad-hoc debugging convenience -->
-            <groupId>org.ow2.asm</groupId>
-            <artifactId>asm-all</artifactId>
-            <version>5.0.3</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.ow2.asm</groupId>
             <artifactId>asm</artifactId>
-            <version>5.0.3</version>
+            <version>7.1</version>
         </dependency>
         <dependency>
             <groupId>org.mockito</groupId>
-            <artifactId>mockito-all</artifactId>
-            <version>1.10.19</version>
+            <artifactId>mockito-core</artifactId>
+            <version>2.7.9</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/lib/src/main/java/net/fushizen/invokedynamic/proxy/DynamicProxy.java b/lib/src/main/java/net/fushizen/invokedynamic/proxy/DynamicProxy.java
index f3ecb6d..685999c 100644
--- a/lib/src/main/java/net/fushizen/invokedynamic/proxy/DynamicProxy.java
+++ b/lib/src/main/java/net/fushizen/invokedynamic/proxy/DynamicProxy.java
@@ -419,9 +419,11 @@ private static void emitMethod(
         int access = ACC_PROTECTED;
         ConcreteMethodTracker concreteMethodTracker = new ConcreteMethodTracker();
 
+        boolean isInterface = true;
         for (Method m : contributors) {
             concreteMethodTracker.add(m);
 
+            isInterface &= m.getDeclaringClass().isInterface();
             if (Modifier.PUBLIC == (m.getModifiers() & Modifier.PUBLIC)) {
                 access = ACC_PUBLIC;
             }
@@ -472,7 +474,8 @@ private static void emitMethod(
                     H_INVOKESPECIAL,
                     Type.getInternalName(superMethod.getDeclaringClass()),
                     superMethod.getName(),
-                    Type.getMethodDescriptor(superMethod)
+                    Type.getMethodDescriptor(superMethod),
+                    isInterface
             );
         }