diff --git a/src/Header/AbstractAddressList.php b/src/Header/AbstractAddressList.php
index 76723ce3..33bac068 100644
--- a/src/Header/AbstractAddressList.php
+++ b/src/Header/AbstractAddressList.php
@@ -66,7 +66,7 @@ abstract class AbstractAddressList implements HeaderInterface
      */
     public static function fromString($headerLine)
     {
-        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
 
         // split into name/value
         list($fieldName, $fieldValue) = explode(': ', $headerLine, 2);
@@ -98,7 +98,7 @@ public static function fromString($headerLine)
             if (empty($name)) {
                 $name = null;
             } else {
-                $name = iconv_mime_decode($name, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+                $name = iconv_mime_decode($name, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
             }
 
             if (isset($matches['namedEmail'])) {
diff --git a/src/Header/ContentType.php b/src/Header/ContentType.php
index 83e0f9d2..b41bb3d5 100755
--- a/src/Header/ContentType.php
+++ b/src/Header/ContentType.php
@@ -58,7 +58,7 @@ class ContentType implements HeaderInterface
      */
     public static function fromString($headerLine)
     {
-        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
         list($name, $value) = explode(': ', $headerLine, 2);
 
         // check to ensure proper header type for this factory
diff --git a/src/Header/GenericHeader.php b/src/Header/GenericHeader.php
index abeda9ca..ceb748ba 100644
--- a/src/Header/GenericHeader.php
+++ b/src/Header/GenericHeader.php
@@ -55,7 +55,7 @@ class GenericHeader implements HeaderInterface
      */
     public static function fromString($headerLine)
     {
-        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
         $parts = explode(': ', $headerLine, 2);
         if (count($parts) != 2) {
             throw new Exception\InvalidArgumentException('Header must match with the format "name: value"');
diff --git a/src/Header/GenericMultiHeader.php b/src/Header/GenericMultiHeader.php
index a7938783..60125d56 100644
--- a/src/Header/GenericMultiHeader.php
+++ b/src/Header/GenericMultiHeader.php
@@ -40,7 +40,7 @@ class GenericMultiHeader extends GenericHeader implements MultipleHeadersInterfa
      */
     public static function fromString($headerLine)
     {
-        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
         $parts = explode(': ', $headerLine, 2);
         if (count($parts) != 2) {
             throw new Exception\InvalidArgumentException('Header must match with the format "name: value"');
diff --git a/src/Header/Sender.php b/src/Header/Sender.php
index 1bbdad82..8f707eba 100644
--- a/src/Header/Sender.php
+++ b/src/Header/Sender.php
@@ -53,7 +53,7 @@ class Sender implements HeaderInterface
      */
     public static function fromString($headerLine)
     {
-        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
         list($name, $value) = explode(': ', $headerLine, 2);
 
         // check to ensure proper header type for this factory
@@ -69,7 +69,7 @@ public static function fromString($headerLine)
             if (empty($name)) {
                 $name = null;
             } else {
-                $name = iconv_mime_decode($name, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+                $name = iconv_mime_decode($name, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
             }
             $header->setAddress($matches['email'], $name);
         }
diff --git a/src/Header/Subject.php b/src/Header/Subject.php
index 6adeef83..8b930d68 100644
--- a/src/Header/Subject.php
+++ b/src/Header/Subject.php
@@ -51,7 +51,7 @@ class Subject implements UnstructuredInterface
      */
     public static function fromString($headerLine)
     {
-        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR);
+        $headerLine = iconv_mime_decode($headerLine, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8');
         list($name, $value) = explode(': ', $headerLine, 2);
 
         // check to ensure proper header type for this factory
diff --git a/test/Header/HeaderWrapTest.php b/test/Header/HeaderWrapTest.php
index 8abf02ed..95959004 100644
--- a/test/Header/HeaderWrapTest.php
+++ b/test/Header/HeaderWrapTest.php
@@ -61,7 +61,7 @@ public function testWrapUnstructuredHeaderMime()
 
         $test = HeaderWrap::wrap($string, $header);
         $this->assertEquals($expected, $test);
-        $this->assertEquals($string, iconv_mime_decode($test));
+        $this->assertEquals($string, iconv_mime_decode($test, ICONV_MIME_DECODE_CONTINUE_ON_ERROR, 'UTF-8'));
     }
 
     /**
diff --git a/test/Storage/MessageTest.php b/test/Storage/MessageTest.php
index 76bdbe28..3dde469f 100644
--- a/test/Storage/MessageTest.php
+++ b/test/Storage/MessageTest.php
@@ -74,8 +74,7 @@ public function testGetDecodedHeader()
     {
         $message = new Message(array('file' => $this->_file));
 
-        $this->assertEquals($message->from, iconv('UTF-8', iconv_get_encoding('internal_encoding'),
-                                                                   '"Peter Müller" <peter-mueller@example.com>'));
+        $this->assertEquals('"Peter Müller" <peter-mueller@example.com>', $message->from);
     }
 
     public function testGetHeaderAsArray()
@@ -213,9 +212,7 @@ public function testIterator()
     public function testDecodeString()
     {
         $is = Mime\Decode::decodeQuotedPrintable('=?UTF-8?Q?"Peter M=C3=BCller"?= <peter-mueller@example.com>');
-        $should = iconv('UTF-8', iconv_get_encoding('internal_encoding'),
-                        '"Peter Müller" <peter-mueller@example.com>');
-        $this->assertEquals($is, $should);
+        $this->assertEquals('"Peter Müller" <peter-mueller@example.com>', $is);
     }
 
     public function testSplitHeader()