diff --git a/core/src/main/java/ch/dissem/bitmessage/entity/payload/Pubkey.java b/core/src/main/java/ch/dissem/bitmessage/entity/payload/Pubkey.java
index 722f60c..789c64c 100644
--- a/core/src/main/java/ch/dissem/bitmessage/entity/payload/Pubkey.java
+++ b/core/src/main/java/ch/dissem/bitmessage/entity/payload/Pubkey.java
@@ -76,16 +76,19 @@ public abstract class Pubkey extends ObjectPayload {
          * Receiving node expects that the RIPE hash encoded in their address preceedes the encrypted message data of msg
          * messages bound for them.
          */
-        INCLUDE_DESTINATION(1 << 30),
+        INCLUDE_DESTINATION(30),
         /**
          * If true, the receiving node does send acknowledgements (rather than dropping them).
          */
-        DOES_ACK(1 << 31);
+        DOES_ACK(31);
 
         private int bit;
 
-        Feature(int bit) {
-            this.bit = bit;
+        Feature(int bitNumber) {
+            // The Bitmessage Protocol Specification starts counting at the most significant bit,
+            // thus the slightly awkward calculation.
+            // https://bitmessage.org/wiki/Protocol_specification#Pubkey_bitfield_features
+            this.bit = 1 << (31 - bitNumber);
         }
 
         public static int bitfield(Feature... features) {
diff --git a/core/src/test/java/ch/dissem/bitmessage/entity/BitmessageAddressTest.java b/core/src/test/java/ch/dissem/bitmessage/entity/BitmessageAddressTest.java
index 9b22589..5d10cdf 100644
--- a/core/src/test/java/ch/dissem/bitmessage/entity/BitmessageAddressTest.java
+++ b/core/src/test/java/ch/dissem/bitmessage/entity/BitmessageAddressTest.java
@@ -20,20 +20,25 @@ import ch.dissem.bitmessage.entity.payload.Pubkey;
 import ch.dissem.bitmessage.entity.payload.V4Pubkey;
 import ch.dissem.bitmessage.entity.valueobject.PrivateKey;
 import ch.dissem.bitmessage.exception.DecryptionFailedException;
-import ch.dissem.bitmessage.utils.Base58;
-import ch.dissem.bitmessage.utils.Bytes;
-import ch.dissem.bitmessage.utils.Strings;
-import ch.dissem.bitmessage.utils.TestUtils;
+import ch.dissem.bitmessage.utils.*;
 import org.junit.Test;
 
 import java.io.IOException;
 import java.util.Arrays;
 
 import static ch.dissem.bitmessage.entity.payload.Pubkey.Feature.DOES_ACK;
+import static ch.dissem.bitmessage.entity.payload.Pubkey.Feature.INCLUDE_DESTINATION;
 import static ch.dissem.bitmessage.utils.Singleton.security;
 import static org.junit.Assert.*;
 
-public class BitmessageAddressTest {
+public class BitmessageAddressTest extends TestBase {
+    @Test
+    public void ensureFeatureFlagIsCalculatedCorrectly() {
+        assertEquals(1, Pubkey.Feature.bitfield(DOES_ACK));
+        assertEquals(2, Pubkey.Feature.bitfield(INCLUDE_DESTINATION));
+        assertEquals(3, Pubkey.Feature.bitfield(DOES_ACK, INCLUDE_DESTINATION));
+    }
+
     @Test
     public void ensureBase58DecodesCorrectly() {
         assertHexEquals("800C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D507A5B8D",
@@ -61,6 +66,7 @@ public class BitmessageAddressTest {
     public void ensureIdentityCanBeCreated() {
         BitmessageAddress address = new BitmessageAddress(new PrivateKey(false, 1, 1000, 1000, DOES_ACK));
         assertNotNull(address.getPubkey());
+        assertTrue(address.has(DOES_ACK));
     }
 
     @Test
@@ -90,6 +96,7 @@ public class BitmessageAddressTest {
         }
 
         assertArrayEquals(Bytes.fromHex("007402be6e76c3cb87caa946d0c003a3d4d8e1d5"), pubkey.getRipe());
+        assertTrue(address.has(DOES_ACK));
     }
 
     @Test
@@ -104,6 +111,7 @@ public class BitmessageAddressTest {
         } catch (Exception e) {
             fail(e.getMessage());
         }
+        assertTrue(address.has(DOES_ACK));
     }
 
     @Test
diff --git a/repositories/src/test/java/ch/dissem/bitmessage/repository/JdbcAddressRepositoryTest.java b/repositories/src/test/java/ch/dissem/bitmessage/repository/JdbcAddressRepositoryTest.java
index bd91329..1975d43 100644
--- a/repositories/src/test/java/ch/dissem/bitmessage/repository/JdbcAddressRepositoryTest.java
+++ b/repositories/src/test/java/ch/dissem/bitmessage/repository/JdbcAddressRepositoryTest.java
@@ -17,12 +17,14 @@
 package ch.dissem.bitmessage.repository;
 
 import ch.dissem.bitmessage.entity.BitmessageAddress;
+import ch.dissem.bitmessage.entity.payload.Pubkey;
 import ch.dissem.bitmessage.entity.valueobject.PrivateKey;
 import org.junit.Before;
 import org.junit.Test;
 
 import java.util.List;
 
+import static ch.dissem.bitmessage.entity.payload.Pubkey.Feature.DOES_ACK;
 import static org.junit.Assert.*;
 
 public class JdbcAddressRepositoryTest extends TestBase {
@@ -46,7 +48,7 @@ public class JdbcAddressRepositoryTest extends TestBase {
         repo.save(new BitmessageAddress(CONTACT_B));
         repo.save(new BitmessageAddress(CONTACT_C));
 
-        BitmessageAddress identityA = new BitmessageAddress(new PrivateKey(false, 1, 1000, 1000));
+        BitmessageAddress identityA = new BitmessageAddress(new PrivateKey(false, 1, 1000, 1000, DOES_ACK));
         repo.save(identityA);
         IDENTITY_A = identityA.getAddress();
         BitmessageAddress identityB = new BitmessageAddress(new PrivateKey(false, 1, 1000, 1000));
@@ -68,6 +70,7 @@ public class JdbcAddressRepositoryTest extends TestBase {
         assertEquals(4, identity.getVersion());
         assertEquals(identity, repo.findIdentity(identity.getTag()));
         assertNull(repo.findContact(identity.getTag()));
+        assertTrue(identity.has(Pubkey.Feature.DOES_ACK));
     }
 
     @Test