diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 0557374..e6c9682 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -5,7 +5,7 @@
 Dave Engberg <engberg@gmail.com>
 -JavaBean/JavaDoc enhancements
 
-Andrew McGeachie <geech@evernote.com>
+Andrew McGeachie <geechorama@gmail.com>
 -Cocoa/Objective-C support
 
 Ben Maurer <bmaurer@andrew.cmu.edu>
diff --git a/compiler/cpp/src/generate/t_cocoa_generator.cc b/compiler/cpp/src/generate/t_cocoa_generator.cc
index c44d061..fe28a7a 100644
--- a/compiler/cpp/src/generate/t_cocoa_generator.cc
+++ b/compiler/cpp/src/generate/t_cocoa_generator.cc
@@ -928,15 +928,24 @@
     const vector<t_field*>& fields = arg_struct->get_members();
     vector<t_field*>::const_iterator fld_iter;
     for (fld_iter = fields.begin(); fld_iter != fields.end(); ++fld_iter) {
+      string fieldName = (*fld_iter)->get_name();
+      if (type_can_be_null((*fld_iter)->get_type())) {
+        out << indent() << "if (" << fieldName << " != nil)";
+        scope_up(out);
+      }
       out <<
-        indent() << "[outProtocol writeFieldBeginWithName: @\"" << (*fld_iter)->get_name() << "\""
+        indent() << "[outProtocol writeFieldBeginWithName: @\"" << fieldName << "\""
         " type: " << type_to_enum((*fld_iter)->get_type()) <<
         " fieldID: " << (*fld_iter)->get_key() << "];" << endl;
 
-      generate_serialize_field(out, *fld_iter, (*fld_iter)->get_name());
+      generate_serialize_field(out, *fld_iter, fieldName);
 
       out <<
         indent() << "[outProtocol writeFieldEnd];" << endl;
+
+      if (type_can_be_null((*fld_iter)->get_type())) {
+        scope_down(out);
+      }
     }
 
     out <<
diff --git a/lib/cocoa/TBinaryProtocol.m b/lib/cocoa/TBinaryProtocol.m
index 2d2ca8e..ba7808c 100644
--- a/lib/cocoa/TBinaryProtocol.m
+++ b/lib/cocoa/TBinaryProtocol.m
@@ -24,6 +24,13 @@
 }
 
 
+- (void) dealloc
+{
+  [mTransport release];
+  [super dealloc];
+}
+
+
 - (id <TTransport>) transport
 {
   return mTransport;
@@ -332,12 +339,18 @@
   [self writeI64: *((int64_t *) &value)];
 }
 
+
 - (void) writeString: (NSString *) value
 {
-  const char * utf8Bytes = [value UTF8String];
-  size_t length = strlen(utf8Bytes);
-  [self writeI32: length];
-  [mTransport write: (uint8_t *) utf8Bytes offset: 0 length: length];
+  if (value != nil) {
+    const char * utf8Bytes = [value UTF8String];
+    size_t length = strlen(utf8Bytes);
+    [self writeI32: length];
+    [mTransport write: (uint8_t *) utf8Bytes offset: 0 length: length];
+  } else {
+    // instead of crashing when we get null, let's write out a zero length string
+    [self writeI32: 0];
+  }
 }