diff --git a/lib/mongo/util/bson.rb b/lib/mongo/util/bson.rb
index 545fa1b..49859fa 100644
--- a/lib/mongo/util/bson.rb
+++ b/lib/mongo/util/bson.rb
@@ -287,12 +287,17 @@ class BSON
     buf.put(BINARY)
     self.class.serialize_cstr(buf, key)
 
-    bytes = if RUBY_VERSION >= '1.9'
-              val.bytes.to_a
+    bytes = case val
+            when ByteBuffer
+              val.to_a
             else
-              a = []
-              val.each_byte { |byte| a << byte }
-              a
+              if RUBY_VERSION >= '1.9'
+                val.bytes.to_a
+              else
+                a = []
+                val.each_byte { |byte| a << byte }
+                a
+              end
             end
 
     num_bytes = bytes.length
@@ -422,7 +427,7 @@ class BSON
       NUMBER_INT
     when Numeric
       NUMBER
-    when XGen::Mongo::Driver::Binary # must be before String
+    when XGen::Mongo::Driver::Binary, ByteBuffer # must be before String
       BINARY
     when String
       # magic awful stuff - the DB requires that a where clause is sent as CODE
diff --git a/mongo-ruby-driver.gemspec b/mongo-ruby-driver.gemspec
index d17c529..be656f0 100644
--- a/mongo-ruby-driver.gemspec
+++ b/mongo-ruby-driver.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name = 'mongo'
-  s.version = '0.2.6'
+  s.version = '0.2.7'
   s.platform = Gem::Platform::RUBY
   s.summary = 'Simple pure-Ruby driver for the 10gen Mongo DB'
   s.description = 'A pure-Ruby driver for the 10gen Mongo DB. For more information about Mongo, see http://www.mongodb.org.'
diff --git a/tests/test_bson.rb b/tests/test_bson.rb
index 349007e..b4b9bbe 100644
--- a/tests/test_bson.rb
+++ b/tests/test_bson.rb
@@ -125,6 +125,18 @@ class BSONTest < Test::Unit::TestCase
     assert_equal 'binstring', doc2['bin']
   end
 
+#   def test_binary_byte_buffer
+#     bb = ByteBuffer.new
+#     10.times { |i| bb.put(i) }
+#     doc = {'bin' => bb}
+#     @b.serialize(doc)
+#     doc2 = @b.deserialize
+
+#     doc2_bytes = []
+#     doc2['bin'].each_byte { |b| doc2_bytes << b }
+#     assert_equal bb.to_a, doc2_bytes
+#   end
+
   def test_undefined
     doc = {'undef' => Undefined.new}
     @b.serialize(doc)