diff --git a/conf/cassandra.yaml b/conf/cassandra.yaml
index 93bba5fe1e..16d9e25746 100644
--- a/conf/cassandra.yaml
+++ b/conf/cassandra.yaml
@@ -66,7 +66,7 @@ max_hints_delivery_threads: 2
 # - PasswordAuthenticator relies on username/password pairs to authenticate
 #   users. It keeps usernames and hashed passwords in system_auth.credentials table.
 #   Please increase system_auth keyspace replication factor if you use this authenticator.
-authenticator: org.apache.cassandra.auth.AllowAllAuthenticator
+authenticator: AllowAllAuthenticator
 
 # Authorization backend, implementing IAuthorizer; used to limit access/provide permissions
 # Out of the box, Cassandra provides org.apache.cassandra.auth.{AllowAllAuthorizer,
@@ -75,7 +75,7 @@ authenticator: org.apache.cassandra.auth.AllowAllAuthenticator
 # - AllowAllAuthorizer allows any action to any user - set it to disable authorization.
 # - CassandraAuthorizer stores permissions in system_auth.permissions table. Please
 #   increase system_auth keyspace replication factor if you use this authorizer.
-authorizer: org.apache.cassandra.auth.AllowAllAuthorizer
+authorizer: AllowAllAuthorizer
 
 # Validity period for permissions cache (fetching permissions can be an
 # expensive operation depending on the authorizer, CassandraAuthorizer is
diff --git a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
index 4d6abaeb11..a01577418c 100644
--- a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
+++ b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
@@ -188,10 +188,10 @@ public class DatabaseDescriptor
 
         /* Authentication and authorization backend, implementing IAuthenticator and IAuthorizer */
         if (conf.authenticator != null)
-            authenticator = FBUtilities.construct(conf.authenticator, "authenticator");
+            authenticator = FBUtilities.newAuthenticator(conf.authenticator);
 
         if (conf.authorizer != null)
-            authorizer = FBUtilities.construct(conf.authorizer, "authorizer");
+            authorizer = FBUtilities.newAuthorizer(conf.authorizer);
 
         if (conf.internode_authenticator != null)
             internodeAuthenticator = FBUtilities.construct(conf.internode_authenticator, "internode_authenticator");
diff --git a/src/java/org/apache/cassandra/utils/FBUtilities.java b/src/java/org/apache/cassandra/utils/FBUtilities.java
index 027f74ad91..8a5572e944 100644
--- a/src/java/org/apache/cassandra/utils/FBUtilities.java
+++ b/src/java/org/apache/cassandra/utils/FBUtilities.java
@@ -41,12 +41,14 @@ import org.apache.commons.lang.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import org.apache.cassandra.exceptions.ConfigurationException;
+import org.apache.cassandra.auth.IAuthenticator;
+import org.apache.cassandra.auth.IAuthorizer;
 import org.apache.cassandra.config.DatabaseDescriptor;
 import org.apache.cassandra.db.DecoratedKey;
 import org.apache.cassandra.dht.IPartitioner;
 import org.apache.cassandra.dht.Range;
 import org.apache.cassandra.dht.Token;
+import org.apache.cassandra.exceptions.ConfigurationException;
 import org.apache.cassandra.io.IVersionedSerializer;
 import org.apache.cassandra.io.util.DataOutputBuffer;
 import org.apache.cassandra.io.util.FileUtils;
@@ -413,6 +415,20 @@ public class FBUtilities
         return FBUtilities.construct(offheap_allocator, "off-heap allocator");
     }
 
+    public static IAuthorizer newAuthorizer(String className) throws ConfigurationException
+    {
+        if (!className.contains("."))
+            className = "org.apache.cassandra.auth." + className;
+        return FBUtilities.construct(className, "authorizer");
+    }
+
+    public static IAuthenticator newAuthenticator(String className) throws ConfigurationException
+    {
+        if (!className.contains("."))
+            className = "org.apache.cassandra.auth." + className;
+        return FBUtilities.construct(className, "authenticator");
+    }
+
     /**
      * @return The Class for the given name.
      * @param classname Fully qualified classname.