diff --git a/src/Httpful/Mime.php b/src/Httpful/Mime.php
index 1a7c456..cc28c85 100644
--- a/src/Httpful/Mime.php
+++ b/src/Httpful/Mime.php
@@ -8,15 +8,16 @@
  */
 class Mime
 {
-    const JSON  = 'application/json';
-    const XML   = 'application/xml';
-    const XHTML = 'application/html+xml';
-    const FORM  = 'application/x-www-form-urlencoded';
-    const PLAIN = 'text/plain';
-    const JS    = 'text/javascript';
-    const HTML  = 'text/html';
-    const YAML  = 'application/x-yaml';
-    const CSV   = 'text/csv';
+    const JSON    = 'application/json';
+    const XML     = 'application/xml';
+    const XHTML   = 'application/html+xml';
+    const FORM    = 'application/x-www-form-urlencoded';
+    const UPLOAD  = 'multipart/form-data';
+    const PLAIN   = 'text/plain';
+    const JS      = 'text/javascript';
+    const HTML    = 'text/html';
+    const YAML    = 'application/x-yaml';
+    const CSV     = 'text/csv';
 
     /**
      * Map short name for a mime type
@@ -28,6 +29,7 @@ class Mime
         'form'      => self::FORM,
         'plain'     => self::PLAIN,
         'text'      => self::PLAIN,
+        'upload'      => self::UPLOAD,
         'html'      => self::HTML,
         'xhtml'     => self::XHTML,
         'js'        => self::JS,
diff --git a/src/Httpful/Request.php b/src/Httpful/Request.php
index c66ff09..0b9eb20 100644
--- a/src/Httpful/Request.php
+++ b/src/Httpful/Request.php
@@ -199,7 +199,7 @@ public function send()
             $this->_curlPrep();
 
         $result = curl_exec($this->_ch);
-
+        
         if ($result === false) {
             $this->_error(curl_error($this->_ch));
             throw new ConnectionErrorException('Unable to connect.');
@@ -333,6 +333,9 @@ public function mime($mime)
     {
         if (empty($mime)) return $this;
         $this->content_type = $this->expected_type = Mime::getFullMime($mime);
+        if($this->isUpload()) {
+            $this->neverSerializePayload();
+        }
         return $this;
     }
     // @alias of mime
@@ -374,6 +377,15 @@ public function expectsType($mime)
     {
         return $this->expects($mime);
     }
+    
+    public function attach($files) {
+        foreach ($files as $key => $file) {
+            $this->payload[$key] = "@{$file}";
+        }
+
+        $this->sendsType(Mime::UPLOAD);
+        return $this;
+    }
 
     /**
      * @return Request this
@@ -383,6 +395,9 @@ public function contentType($mime)
     {
         if (empty($mime)) return $this;
         $this->content_type  = Mime::getFullMime($mime);
+        if($this->isUpload()) {
+            $this->neverSerializePayload();
+        }
         return $this;
     }
     // @alias of contentType
@@ -437,7 +452,7 @@ public function useProxy($proxy_host, $proxy_port = 80, $auth_type = null, $auth
      * @return is this request setup for using proxy?
      */
     public function hasProxy(){
-        return is_string($this->additional_curl_opts[CURLOPT_PROXY]);
+        return isset($this->additional_curl_opts[CURLOPT_PROXY]) && is_string($this->additional_curl_opts[CURLOPT_PROXY]);
     }
 
     /**
@@ -794,7 +809,8 @@ public function _curlPrep()
         if (isset($this->payload)) {
             $this->serialized_payload = $this->_serializePayload($this->payload);
             curl_setopt($ch, CURLOPT_POSTFIELDS, $this->serialized_payload);
-            $this->headers['Content-Length'] = strlen($this->serialized_payload);
+            if(!$this->isUpload())
+                $this->headers['Content-Length'] = strlen($this->serialized_payload) ;
         }
 
         $headers = array();
@@ -821,7 +837,7 @@ public function _curlPrep()
         }
 
         // Solve a bug on squid proxy, NONE/411 when miss content length
-        if (!isset($this->headers['Content-Length'])) {
+        if (!isset($this->headers['Content-Length']) && !$this->isUpload()) {
             $this->headers['Content-Length'] = 0;
         }
 
@@ -850,11 +866,15 @@ public function _curlPrep()
         foreach ($this->additional_curl_opts as $curlopt => $curlval) {
             curl_setopt($ch, $curlopt, $curlval);
         }
-
+        
         $this->_ch = $ch;
 
         return $this;
     }
+    
+    public function isUpload() {
+        return Mime::UPLOAD == $this->content_type;
+    }
 
     public function buildUserAgent() {
         $user_agent = 'User-Agent: Httpful/' . Httpful::VERSION . ' (cURL/';
diff --git a/tests/Httpful/HttpfulTest.php b/tests/Httpful/HttpfulTest.php
index ac2ab54..8a3115c 100644
--- a/tests/Httpful/HttpfulTest.php
+++ b/tests/Httpful/HttpfulTest.php
@@ -91,12 +91,14 @@ function testShortMime()
         $this->assertEquals(Mime::XML,   Mime::getFullMime('xml'));
         $this->assertEquals(Mime::HTML,  Mime::getFullMime('html'));
         $this->assertEquals(Mime::CSV,  Mime::getFullMime('csv'));
+        $this->assertEquals(Mime::UPLOAD,  Mime::getFullMime('upload'));
 
         // Valid long ones
         $this->assertEquals(Mime::JSON, Mime::getFullMime(Mime::JSON));
         $this->assertEquals(Mime::XML,  Mime::getFullMime(Mime::XML));
         $this->assertEquals(Mime::HTML, Mime::getFullMime(Mime::HTML));
         $this->assertEquals(Mime::CSV, Mime::getFullMime(Mime::CSV));
+        $this->assertEquals(Mime::UPLOAD, Mime::getFullMime(Mime::UPLOAD));
 
         // No false positives
         $this->assertNotEquals(Mime::XML,  Mime::getFullMime(Mime::HTML));
@@ -293,7 +295,36 @@ function testParsingContentTypeCharset()
         $this->assertEquals($response->content_type, 'text/plain');
         $this->assertEquals($response->charset, 'utf-8');
     }
-
+    
+    function testParsingContentTypeUpload()
+    {
+        $req = Request::init();
+        
+        $req->sendsType(Mime::UPLOAD);
+        // $response = new Response(SAMPLE_JSON_RESPONSE, "", $req);
+        // // Check default content type of iso-8859-1
+        $this->assertEquals($req->content_type, 'multipart/form-data');
+    }
+    
+    function testAttach() {
+        $req = Request::init();
+        
+        $req->attach(array('index' => '/dir/filename'));
+        // $response = new Response(SAMPLE_JSON_RESPONSE, "", $req);
+        // // Check default content type of iso-8859-1
+        $this->assertEquals($req->payload['index'], '@/dir/filename');
+        $this->assertEquals($req->content_type, Mime::UPLOAD);
+        $this->assertEquals($req->serialize_payload_method, Request::SERIALIZE_PAYLOAD_NEVER);
+    }
+    
+    function testIsUpload() {
+        $req = Request::init();
+        
+        $req->sendsType(Mime::UPLOAD);
+        
+        $this->assertTrue($req->isUpload());
+    }
+    
     function testEmptyResponseParse()
     {
         $req = Request::init()->sendsAndExpects(Mime::JSON);