diff --git a/core/src/main/java/org/jclouds/rest/internal/RestAnnotationProcessor.java b/core/src/main/java/org/jclouds/rest/internal/RestAnnotationProcessor.java
index b6f7b95403..75f96b24c9 100644
--- a/core/src/main/java/org/jclouds/rest/internal/RestAnnotationProcessor.java
+++ b/core/src/main/java/org/jclouds/rest/internal/RestAnnotationProcessor.java
@@ -135,6 +135,7 @@ import org.jclouds.util.Strings2;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Function;
 import com.google.common.base.Functions;
+import com.google.common.base.Preconditions;
 import com.google.common.base.Predicate;
 import com.google.common.base.Predicates;
 import com.google.common.base.Throwables;
@@ -1093,7 +1094,9 @@ public class RestAnnotationProcessor<T> {
                options.contentType(param.contentType());
             if (!PartParam.NO_FILENAME.equals(param.filename()))
                options.filename(Strings2.replaceTokens(param.filename(), iterable));
-            Part part = Part.create(param.name(), newPayload(args[entry.getKey()]), options);
+            Object arg = args[entry.getKey()];
+            Preconditions.checkNotNull(arg, param.name());
+            Part part = Part.create(param.name(), newPayload(arg), options);
             parts.add(part);
          }
       }
@@ -1200,7 +1203,9 @@ public class RestAnnotationProcessor<T> {
                ParamParser extractor = (ParamParser) extractors.iterator().next();
                paramValue = injector.getInstance(extractor.value()).apply(args[entry.getKey()]);
             } else {
-               paramValue = args[entry.getKey()].toString();
+               Object pvo = args[entry.getKey()];
+               Preconditions.checkNotNull(pvo, paramKey);
+               paramValue = pvo.toString();
             }
             formParamValues.put(paramKey, paramValue);
          }
diff --git a/core/src/test/java/org/jclouds/rest/internal/RestAnnotationProcessorTest.java b/core/src/test/java/org/jclouds/rest/internal/RestAnnotationProcessorTest.java
index f98fb7ab18..f943e2ee98 100644
--- a/core/src/test/java/org/jclouds/rest/internal/RestAnnotationProcessorTest.java
+++ b/core/src/test/java/org/jclouds/rest/internal/RestAnnotationProcessorTest.java
@@ -143,6 +143,7 @@ import org.jclouds.rest.binders.BindToJsonPayload;
 import org.jclouds.rest.binders.BindToStringPayload;
 import org.jclouds.rest.config.RestClientModule;
 import org.jclouds.util.Strings2;
+import org.testng.Assert;
 import org.testng.annotations.BeforeClass;
 import org.testng.annotations.DataProvider;
 import org.testng.annotations.Test;
@@ -552,6 +553,9 @@ public class RestAnnotationProcessorTest extends BaseRestClientTest {
       @POST
       void post(@Nullable @BinderParam(BindToStringPayload.class) String content);
 
+      @POST
+      void postNonnull(@BinderParam(BindToStringPayload.class) String content);
+      
       @POST
       public void postAsJson(@BinderParam(BindToJsonPayload.class) String content);
 
@@ -587,7 +591,7 @@ public class RestAnnotationProcessorTest extends BaseRestClientTest {
       assertPayloadEquals(request, "data", "application/unknown", false);
    }
 
-   public void testCreatePostRequestNullOk() throws SecurityException, NoSuchMethodException, IOException {
+   public void testCreatePostRequestNullOk1() throws SecurityException, NoSuchMethodException, IOException {
       Method method = TestPost.class.getMethod("post", String.class);
       HttpRequest request = factory(TestPost.class).createRequest(method);
 
@@ -596,6 +600,37 @@ public class RestAnnotationProcessorTest extends BaseRestClientTest {
       assertPayloadEquals(request, null, "application/unknown", false);
    }
 
+   public void testCreatePostRequestNullOk2() throws SecurityException, NoSuchMethodException, IOException {
+      Method method = TestPost.class.getMethod("post", String.class);
+      HttpRequest request = factory(TestPost.class).createRequest(method, (String)null);
+
+      assertRequestLineEquals(request, "POST http://localhost:9999 HTTP/1.1");
+      assertNonPayloadHeadersEqual(request, "");
+      assertPayloadEquals(request, null, "application/unknown", false);
+   }
+
+   //FIXME the following two tests fail, suggesting that the tests above aren't actually testing Nullable
+   //but rather indicates that RestAnnotationProcessor.decorateRequest silently ignores nulls
+//   public void testCreatePostRequestNullNotOk1() throws SecurityException, NoSuchMethodException, IOException {
+//      Method method = TestPost.class.getMethod("postNonnull", String.class);
+//      try {
+//         HttpRequest request = factory(TestPost.class).createRequest(method);
+//         Assert.fail("call should have failed with illegal null parameter, not permitted "+request+" to be created");
+//      } catch (NullPointerException e) {
+////         Assert.assertTrue(e.toString().indexOf("???")>=0, "Error message should have referred to parameter 'fooble': "+e);
+//      }
+//   }
+//
+//   public void testCreatePostRequestNullNotOk2() throws SecurityException, NoSuchMethodException, IOException {
+//      Method method = TestPost.class.getMethod("postNonnull", String.class);
+//      try {
+//         HttpRequest request = factory(TestPost.class).createRequest(method, (String)null);
+//         Assert.fail("call should have failed with illegal null parameter, not permitted "+request+" to be created");
+//      } catch (NullPointerException e) {
+//         //      Assert.assertTrue(e.toString().indexOf("???")>=0, "Error message should have referred to parameter 'fooble': "+e);
+//      }
+//   }
+
    public void testCreatePostJsonRequest() throws SecurityException, NoSuchMethodException, IOException {
       Method method = TestPost.class.getMethod("postAsJson", String.class);
       HttpRequest request = factory(TestPost.class).createRequest(method, "data");
@@ -684,6 +719,17 @@ public class RestAnnotationProcessorTest extends BaseRestClientTest {
                         "----JCLOUDS----\r\n", "multipart/form-data; boundary=--JCLOUDS--", false);
    }
 
+   public void testMultipartWithStringPartNullNotOkay() throws SecurityException, NoSuchMethodException, IOException {
+      Method method = TestMultipartForm.class.getMethod("withStringPart", String.class);
+      try {
+         GeneratedHttpRequest<TestMultipartForm> httpRequest = factory(TestMultipartForm.class).createRequest(method,
+               (String)null);
+         Assert.fail("call should have failed with illegal null parameter, not permitted "+httpRequest+" to be created");
+      } catch (NullPointerException e) {
+         Assert.assertTrue(e.toString().indexOf("fooble")>=0, "Error message should have referred to parameter 'fooble': "+e);
+      }
+   }
+
    public void testMultipartWithParamStringPart() throws SecurityException, NoSuchMethodException, IOException {
       Method method = TestMultipartForm.class.getMethod("withParamStringPart", String.class, String.class);
       GeneratedHttpRequest<TestMultipartForm> httpRequest = factory(TestMultipartForm.class).createRequest(method,
@@ -702,6 +748,17 @@ public class RestAnnotationProcessorTest extends BaseRestClientTest {
                         "----JCLOUDS----\r\n", "multipart/form-data; boundary=--JCLOUDS--", false);
    }
 
+   public void testMultipartWithParamStringPartNullNotOk() throws SecurityException, NoSuchMethodException, IOException {
+      Method method = TestMultipartForm.class.getMethod("withParamStringPart", String.class, String.class);
+      try {
+         GeneratedHttpRequest<TestMultipartForm> httpRequest = factory(TestMultipartForm.class).createRequest(method,
+               null, "foobledata");
+         Assert.fail("call should have failed with illegal null parameter, not permitted "+httpRequest+" to be created");
+      } catch (NullPointerException e) {
+         Assert.assertTrue(e.toString().indexOf("name")>=0, "Error message should have referred to parameter 'name': "+e);
+      }
+   }
+
    public void testMultipartWithParamFilePart() throws SecurityException, NoSuchMethodException, IOException {
       Method method = TestMultipartForm.class.getMethod("withParamFilePart", String.class, File.class);
       File file = File.createTempFile("foo", "bar");