diff --git a/ext/yajl/yajl_ext.c b/ext/yajl/yajl_ext.c
index 25120100..678907ee 100644
--- a/ext/yajl/yajl_ext.c
+++ b/ext/yajl/yajl_ext.c
@@ -389,22 +389,25 @@ static int yajl_found_end_array(void * ctx) {
 /*
  * Document-method: new
  *
- * call-seq: new([:symbolize_keys => true, [:allow_comments => false[, :check_utf8 => false]]])
+ * call-seq: new([:symbolize_keys => true, [:allow_comments => false[, :check_utf8 => false]]][, &callback])
  *
  * :symbolize_keys will turn hash keys into Ruby symbols, defaults to false.
  *
  * :allow_comments will turn on/off the check for comments inside the JSON stream, defaults to true.
  *
  * :check_utf8 will validate UTF8 characters found in the JSON stream, defaults to true.
+ *
+ * If a block was passed, it's called when an object has been parsed off the stream. This is especially
+ * useful when parsing a stream of multiple JSON objects.
  */
 static VALUE rb_yajl_parser_new(int argc, VALUE * argv, VALUE klass) {
     yajl_parser_wrapper * wrapper;
     yajl_parser_config cfg;
-    VALUE opts, obj;
+    VALUE opts, blk, obj;
     int allowComments = 1, checkUTF8 = 1, symbolizeKeys = 0;
 
     /* Scan off config vars */
-    if (rb_scan_args(argc, argv, "01", &opts) == 1) {
+    if (rb_scan_args(argc, argv, "01&", &opts, &blk) == 1) {
         Check_Type(opts, T_HASH);
 
         if (rb_hash_aref(opts, sym_allow_comments) == Qfalse) {
@@ -426,7 +429,7 @@ static VALUE rb_yajl_parser_new(int argc, VALUE * argv, VALUE klass) {
     wrapper->objectsFound = 0;
     wrapper->symbolizeKeys = symbolizeKeys;
     wrapper->builderStack = rb_ary_new();
-    wrapper->parse_complete_callback = Qnil;
+    wrapper->parse_complete_callback = blk;
     rb_obj_call_init(obj, 0, 0);
     return obj;
 }
@@ -434,7 +437,7 @@ static VALUE rb_yajl_parser_new(int argc, VALUE * argv, VALUE klass) {
 /*
  * Document-method: initialize
  *
- * call-seq: new([:symbolize_keys => true, [:allow_comments => false[, :check_utf8 => false]]])
+ * call-seq: new([:symbolize_keys => true, [:allow_comments => false[, :check_utf8 => false]]][, &callback])
  *
  * :symbolize_keys will turn hash keys into Ruby symbols, defaults to false.
  *
@@ -462,7 +465,7 @@ static VALUE rb_yajl_parser_init(int argc, VALUE * argv, VALUE self) {
  * reading off of a socket directly.
  *
  * If a block was passed, it's called when an object has been parsed off the stream. This is especially
- * usefull when parsing a stream of multiple JSON objects.
+ * useful when parsing a stream of multiple JSON objects.
  *
  * NOTE: you can optionally assign the +on_parse_complete+ callback, and it will be called the same way the optional
  * block is for this method.
@@ -572,27 +575,29 @@ static unsigned char * defaultIndentString = (unsigned char *)"  ";
 /*
  * Document-method: new
  *
- * call-seq: initialize([:pretty => false[, :indent => '  '][, :terminator => "\n"]])
-  *
-  * :pretty will enable/disable beautifying or "pretty priting" the output string.
-  *
-  * :indent is the character(s) used to indent the output string.
-  *
-  * :terminator allows you to specify a character to be used as the termination character after a full JSON string has been generated by
-  * the encoder. This would be especially useful when encoding in chunks (via a block or callback during the encode process), to be able to
-  * determine when the last chunk of the current encode is sent.
-  * If you specify this option to be nil, it will be ignored if encoding directly to an IO or simply returning a string. But if a block is used,
-  * the encoder will still pass it - I hope that makes sense ;).
+ * call-seq: new([:pretty => false[, :indent => '  '][, :terminator => "\n"]][, &callback])
+ *
+ * :pretty will enable/disable beautifying or "pretty priting" the output string.
+ *
+ * :indent is the character(s) used to indent the output string.
+ *
+ * :terminator allows you to specify a character to be used as the termination character after a full JSON string has been generated by
+ * the encoder. This would be especially useful when encoding in chunks (via a block or callback during the encode process), to be able to
+ * determine when the last chunk of the current encode is sent.
+ * If you specify this option to be nil, it will be ignored if encoding directly to an IO or simply returning a string. But if a block is used,
+ * the encoder will still pass it - I hope that makes sense ;).
+ *
+ * If an optional block is passed, it's called when encoding is complete and passed the resulting JSON string
  */
 static VALUE rb_yajl_encoder_new(int argc, VALUE * argv, VALUE klass) {
     yajl_encoder_wrapper * wrapper;
     yajl_gen_config cfg;
-    VALUE opts, obj, indent;
+    VALUE opts, blk, obj, indent;
     unsigned char *indentString = NULL, *actualIndent = NULL;
     int beautify = 0, htmlSafe = 0;
 
     /* Scan off config vars */
-    if (rb_scan_args(argc, argv, "01", &opts) == 1) {
+    if (rb_scan_args(argc, argv, "01&", &opts, &blk) == 1) {
         Check_Type(opts, T_HASH);
 
         if (rb_hash_aref(opts, sym_pretty) == Qtrue) {
@@ -621,7 +626,7 @@ static VALUE rb_yajl_encoder_new(int argc, VALUE * argv, VALUE klass) {
     obj = Data_Make_Struct(klass, yajl_encoder_wrapper, yajl_encoder_wrapper_mark, yajl_encoder_wrapper_free, wrapper);
     wrapper->indentString = actualIndent;
     wrapper->encoder = yajl_gen_alloc(&cfg, NULL);
-    wrapper->on_progress_callback = Qnil;
+    wrapper->on_progress_callback = blk;
     if (opts != Qnil && rb_funcall(opts, intern_has_key, 1, sym_terminator) == Qtrue) {
         wrapper->terminator = rb_hash_aref(opts, sym_terminator);
 #ifdef HAVE_RUBY_ENCODING_H
@@ -639,7 +644,7 @@ static VALUE rb_yajl_encoder_new(int argc, VALUE * argv, VALUE klass) {
 /*
  * Document-method: initialize
  *
- * call-seq: initialize([:pretty => false[, :indent => '  '][, :terminator => "\n"]])
+ * call-seq: initialize([:pretty => false[, :indent => '  '][, :terminator => "\n"]][, &callback])
  *
  * :pretty will enable/disable beautifying or "pretty priting" the output string.
  *
@@ -702,10 +707,10 @@ static VALUE rb_yajl_encoder_encode(int argc, VALUE * argv, VALUE self) {
             rb_io_write(io, wrapper->terminator);
         }
         return Qnil;
-    } else if (blk != Qnil) {
-        rb_funcall(blk, intern_call, 1, outBuff);
+    } else if (wrapper->on_progress_callback != Qnil) {
+        rb_funcall(wrapper->on_progress_callback, intern_call, 1, outBuff);
         if (wrapper->terminator != 0) {
-            rb_funcall(blk, intern_call, 1, wrapper->terminator);
+            rb_funcall(wrapper->on_progress_callback, intern_call, 1, wrapper->terminator);
         }
         return Qnil;
     } else {
diff --git a/spec/encoding/encoding_spec.rb b/spec/encoding/encoding_spec.rb
index 818f028b..2fc1bb3c 100644
--- a/spec/encoding/encoding_spec.rb
+++ b/spec/encoding/encoding_spec.rb
@@ -132,6 +132,25 @@ def to_s
     output.should == output
   end
 
+  it "should encode with a callback passed via on_progress" do
+    callback = lambda { |str|
+      # no-op
+    }
+    encoder = Yajl::Encoder.new
+    encoder.on_progress = callback
+    callback.should_receive(:call).with('{}')
+    encoder.encode({})
+  end
+
+  it "should encode with a callback passed as block" do
+    callback = lambda { |str|
+      # no-op
+    }
+    encoder = Yajl::Encoder.new(&callback)
+    callback.should_receive(:call).with('{}')
+    encoder.encode({})
+  end
+
   it "should encode with it's class method with :pretty and a tab character indent options set, to an IO" do
     output = "{\n\t\"foo\": 1234\n}"
     obj = {:foo => 1234}
diff --git a/spec/parsing/chunked_spec.rb b/spec/parsing/chunked_spec.rb
index 20248c9a..dd62de6c 100644
--- a/spec/parsing/chunked_spec.rb
+++ b/spec/parsing/chunked_spec.rb
@@ -13,6 +13,15 @@
     @parser.on_parse_complete = @callback
   end
 
+  it "should take the callback as block parameter" do
+    @callback = lambda { |hash|
+      # no-op
+    }
+    @parser = Yajl::Parser.new(&@callback)
+    @callback.should_receive(:call).with(@final)
+    @parser << '[{"abc": 123},{"def": 456}]'
+  end
+
   it "should parse a single chunk" do
     @callback.should_receive(:call).with(@final)
     @parser << '[{"abc": 123},{"def": 456}]'