diff --git a/wp-includes/pomo/entry.php b/wp-includes/pomo/entry.php
index 07ddfd4d11..6432dbedb3 100644
--- a/wp-includes/pomo/entry.php
+++ b/wp-includes/pomo/entry.php
@@ -2,7 +2,7 @@
 /**
  * Contains Translation_Entry class
  *
- * @version $Id: entry.php 406 2010-02-07 11:10:24Z nbachiyski $
+ * @version $Id: entry.php 621 2011-06-13 12:21:50Z nbachiyski $
  * @package pomo
  * @subpackage entry
  */
@@ -65,5 +65,14 @@ class Translation_Entry {
 		// prepend context and EOT, like in MO files
 		return is_null($this->context)? $this->singular : $this->context.chr(4).$this->singular;
 	}
+	
+	function merge_with(&$other) {
+		$this->flags = array_unique( array_merge( $this->flags, $other->flags ) );
+		$this->references = array_unique( array_merge( $this->references, $other->references ) );
+		if ( $this->extracted_comments != $other->extracted_comments ) {
+			$this->extracted_comments .= $other->extracted_comments;
+		}
+		
+	}
 }
 endif;
\ No newline at end of file
diff --git a/wp-includes/pomo/mo.php b/wp-includes/pomo/mo.php
index 72e0e7bf22..683d3ed6a5 100644
--- a/wp-includes/pomo/mo.php
+++ b/wp-includes/pomo/mo.php
@@ -2,7 +2,7 @@
 /**
  * Class for working with MO files
  *
- * @version $Id: mo.php 406 2010-02-07 11:10:24Z nbachiyski $
+ * @version $Id: mo.php 602 2011-01-30 12:43:29Z nbachiyski $
  * @package pomo
  * @subpackage mo
  */
@@ -30,6 +30,20 @@ class MO extends Gettext_Translations {
 	function export_to_file($filename) {
 		$fh = fopen($filename, 'wb');
 		if ( !$fh ) return false;
+		$res = $this->export_to_file_handle( $fh );
+		fclose($fh);
+		return $res;
+	}
+	
+	function export() {
+		$tmp_fh = fopen("php://temp", 'r+');
+		if ( !$tmp_fh ) return false;
+		$this->export_to_file_handle( $tmp_fh );
+		rewind( $tmp_fh );
+		return stream_get_contents( $tmp_fh );
+	}
+	
+	function export_to_file_handle($fh) {
 		$entries = array_filter($this->entries, create_function('$e', 'return !empty($e->translations);'));
 		ksort($entries);
 		$magic = 0x950412de;
@@ -43,7 +57,7 @@ class MO extends Gettext_Translations {
 		fwrite($fh, pack('V*', $magic, $revision, $total, $originals_lenghts_addr,
 			$translations_lenghts_addr, $size_of_hash, $hash_addr));
 		fseek($fh, $originals_lenghts_addr);
-
+		
 		// headers' msgid is an empty string
 		fwrite($fh, pack('VV', 0, $current_addr));
 		$current_addr++;
@@ -55,24 +69,24 @@ class MO extends Gettext_Translations {
 			fwrite($fh, pack('VV', $length, $current_addr));
 			$current_addr += $length + 1; // account for the NULL byte after
 		}
-
+		
 		$exported_headers = $this->export_headers();
 		fwrite($fh, pack('VV', strlen($exported_headers), $current_addr));
 		$current_addr += strlen($exported_headers) + 1;
 		$translations_table = $exported_headers . chr(0);
-
+		
 		foreach($entries as $entry) {
 			$translations_table .= $this->export_translations($entry) . chr(0);
 			$length = strlen($this->export_translations($entry));
 			fwrite($fh, pack('VV', $length, $current_addr));
 			$current_addr += $length + 1;
 		}
-
+		
 		fwrite($fh, $originals_table);
 		fwrite($fh, $translations_table);
-		fclose($fh);
+		return true;
 	}
-
+	
 	function export_original($entry) {
 		//TODO: warnings for control characters
 		$exported = $entry->singular;
@@ -80,12 +94,12 @@ class MO extends Gettext_Translations {
 		if (!is_null($entry->context)) $exported = $entry->context . chr(4) . $exported;
 		return $exported;
 	}
-
+	
 	function export_translations($entry) {
 		//TODO: warnings for control characters
 		return implode(chr(0), $entry->translations);
 	}
-
+	
 	function export_headers() {
 		$exported = '';
 		foreach($this->headers as $header => $value) {
@@ -193,7 +207,7 @@ class MO extends Gettext_Translations {
 	/**
 	 * Build a Translation_Entry from original string and translation strings,
 	 * found in a MO file
-	 *
+	 * 
 	 * @static
 	 * @param string $original original string to translate from MO file. Might contain
 	 * 	0x04 as context separator or 0x00 as singular/plural separator
diff --git a/wp-includes/pomo/po.php b/wp-includes/pomo/po.php
index 8e3eb61151..8320bc1e1d 100644
--- a/wp-includes/pomo/po.php
+++ b/wp-includes/pomo/po.php
@@ -2,7 +2,7 @@
 /**
  * Class for working with PO files
  *
- * @version $Id: po.php 406 2010-02-07 11:10:24Z nbachiyski $
+ * @version $Id: po.php 589 2010-12-18 01:40:57Z nbachiyski $
  * @package pomo
  * @subpackage po
  */
@@ -18,7 +18,8 @@ ini_set('auto_detect_line_endings', 1);
  */
 if ( !class_exists( 'PO' ) ):
 class PO extends Gettext_Translations {
-
+	
+	var $comments_before_headers = '';
 
 	/**
 	 * Exports headers to a PO entry
@@ -31,7 +32,11 @@ class PO extends Gettext_Translations {
 			$header_string.= "$header: $value\n";
 		}
 		$poified = PO::poify($header_string);
-		return rtrim("msgid \"\"\nmsgstr $poified");
+		if ($this->comments_before_headers)
+			$before_headers = $this->prepend_each_line(rtrim($this->comments_before_headers)."\n", '# ');
+		else
+			$before_headers = '';
+		return rtrim("{$before_headers}msgid \"\"\nmsgstr $poified");
 	}
 
 	/**
@@ -75,6 +80,15 @@ class PO extends Gettext_Translations {
 		if (false === $res) return false;
 		return fclose($fh);
 	}
+	
+	/**
+	 * Text to include as a comment before the start of the PO contents
+	 * 
+	 * Doesn't need to include # in the beginning of lines, these are added automatically
+	 */
+	function set_comment_before_headers( $text ) {
+		$this->comments_before_headers = $text;
+	}
 
 	/**
 	 * Formats a string in PO-style
@@ -106,10 +120,10 @@ class PO extends Gettext_Translations {
 		$po = str_replace("$newline$quote$quote", '', $po);
 		return $po;
 	}
-
+	
 	/**
 	 * Gives back the original string from a PO-formatted string
-	 *
+	 * 
 	 * @static
 	 * @param string $string PO-formatted string
 	 * @return string enascaped string
@@ -139,7 +153,7 @@ class PO extends Gettext_Translations {
 	}
 
 	/**
-	 * Inserts $with in the beginning of every new line of $string and
+	 * Inserts $with in the beginning of every new line of $string and 
 	 * returns the modified string
 	 *
 	 * @static
@@ -217,7 +231,7 @@ class PO extends Gettext_Translations {
 		PO::read_line($f, 'clear');
 		return $res !== false;
 	}
-
+	
 	function read_entry($f, $lineno = 0) {
 		$entry = new Translation_Entry();
 		// where were we in the last step
@@ -254,7 +268,7 @@ class PO extends Gettext_Translations {
 					return false;
 				}
 				// add comment
-				$this->add_comment_to_entry($entry, $line);
+				$this->add_comment_to_entry($entry, $line);;
 			} elseif (preg_match('/^msgctxt\s+(".*")/', $line, $m)) {
 				if ($is_final($context)) {
 					PO::read_line($f, 'put-back');
@@ -322,7 +336,7 @@ class PO extends Gettext_Translations {
 		}
 		return array('entry' => $entry, 'lineno' => $lineno);
 	}
-
+	
 	function read_line($f, $action = 'read') {
 		static $last_line = '';
 		static $use_last_line = false;
@@ -339,7 +353,7 @@ class PO extends Gettext_Translations {
 		$use_last_line = false;
 		return $line;
 	}
-
+	
 	function add_comment_to_entry(&$entry, $po_comment_line) {
 		$first_two = substr($po_comment_line, 0, 2);
 		$comment = trim(substr($po_comment_line, 2));
@@ -353,11 +367,11 @@ class PO extends Gettext_Translations {
 			$entry->translator_comments = trim($entry->translator_comments . "\n" . $comment);
 		}
 	}
-
+	
 	function trim_quotes($s) {
 		if ( substr($s, 0, 1) == '"') $s = substr($s, 1);
 		if ( substr($s, -1, 1) == '"') $s = substr($s, 0, -1);
 		return $s;
 	}
 }
-endif;
+endif;
\ No newline at end of file
diff --git a/wp-includes/pomo/streams.php b/wp-includes/pomo/streams.php
index 289cc785a2..efaffa5ae9 100644
--- a/wp-includes/pomo/streams.php
+++ b/wp-includes/pomo/streams.php
@@ -3,26 +3,26 @@
  * Classes, which help reading streams of data from files.
  * Based on the classes from Danilo Segan <danilo@kvota.net>
  *
- * @version $Id: streams.php 406 2010-02-07 11:10:24Z nbachiyski $
+ * @version $Id: streams.php 597 2011-01-16 20:14:36Z nbachiyski $
  * @package pomo
  * @subpackage streams
  */
 
 if ( !class_exists( 'POMO_Reader' ) ):
 class POMO_Reader {
-
+	
 	var $endian = 'little';
 	var $_post = '';
-
+	
 	function POMO_Reader() {
 		$this->is_overloaded = ((ini_get("mbstring.func_overload") & 2) != 0) && function_exists('mb_substr');
 		$this->_pos = 0;
 	}
-
+	
 	/**
 	 * Sets the endianness of the file.
 	 *
-	 * @param string $endian 'big' or 'little'
+	 * @param $endian string 'big' or 'little'
 	 */
 	function setEndian($endian) {
 		$this->endian = $endian;
@@ -57,8 +57,8 @@ class POMO_Reader {
 		$endian_letter = ('big' == $this->endian)? 'N' : 'V';
 		return unpack($endian_letter.$count, $bytes);
 	}
-
-
+	
+	
 	function substr($string, $start, $length) {
 		if ($this->is_overloaded) {
 			return mb_substr($string, $start, $length, 'ascii');
@@ -66,7 +66,7 @@ class POMO_Reader {
 			return substr($string, $start, $length);
 		}
 	}
-
+	
 	function strlen($string) {
 		if ($this->is_overloaded) {
 			return mb_strlen($string, 'ascii');
@@ -74,7 +74,7 @@ class POMO_Reader {
 			return strlen($string);
 		}
 	}
-
+	
 	function str_split($string, $chunk_size) {
 		if (!function_exists('str_split')) {
 			$length = $this->strlen($string);
@@ -86,8 +86,8 @@ class POMO_Reader {
 			return str_split( $string, $chunk_size );
 		}
 	}
-
-
+	
+		
 	function pos() {
 		return $this->_pos;
 	}
@@ -95,7 +95,7 @@ class POMO_Reader {
 	function is_resource() {
 		return true;
 	}
-
+	
 	function close() {
 		return true;
 	}
@@ -106,13 +106,13 @@ if ( !class_exists( 'POMO_FileReader' ) ):
 class POMO_FileReader extends POMO_Reader {
 	function POMO_FileReader($filename) {
 		parent::POMO_Reader();
-		$this->_f = fopen($filename, 'r');
+		$this->_f = fopen($filename, 'rb');
 	}
-
+	
 	function read($bytes) {
 		return fread($this->_f, $bytes);
 	}
-
+	
 	function seekto($pos) {
 		if ( -1 == fseek($this->_f, $pos, SEEK_SET)) {
 			return false;
@@ -120,19 +120,19 @@ class POMO_FileReader extends POMO_Reader {
 		$this->_pos = $pos;
 		return true;
 	}
-
+	
 	function is_resource() {
 		return is_resource($this->_f);
 	}
-
+	
 	function feof() {
 		return feof($this->_f);
 	}
-
+	
 	function close() {
 		return fclose($this->_f);
 	}
-
+	
 	function read_all() {
 		$all = '';
 		while ( !$this->feof() )
@@ -148,9 +148,9 @@ if ( !class_exists( 'POMO_StringReader' ) ):
  * of a physical file.
  */
 class POMO_StringReader extends POMO_Reader {
-
+	
 	var $_str = '';
-
+	
 	function POMO_StringReader($str = '') {
 		parent::POMO_Reader();
 		$this->_str = $str;
@@ -178,7 +178,7 @@ class POMO_StringReader extends POMO_Reader {
 	function read_all() {
 		return $this->substr($this->_str, $this->_pos, $this->strlen($this->_str));
 	}
-
+	
 }
 endif;
 
diff --git a/wp-includes/pomo/translations.php b/wp-includes/pomo/translations.php
index 01be8df42d..465b168316 100644
--- a/wp-includes/pomo/translations.php
+++ b/wp-includes/pomo/translations.php
@@ -2,7 +2,7 @@
 /**
  * Class for a set of entries for translation and their associated headers
  *
- * @version $Id: translations.php 406 2010-02-07 11:10:24Z nbachiyski $
+ * @version $Id: translations.php 590 2010-12-20 19:58:37Z nbachiyski $
  * @package pomo
  * @subpackage translations
  */
@@ -29,6 +29,19 @@ class Translations {
 		$this->entries[$key] = &$entry;
 		return true;
 	}
+	
+	function add_entry_or_merge($entry) {
+		if (is_array($entry)) {
+			$entry = new Translation_Entry($entry);
+		}
+		$key = $entry->key();
+		if (false === $key) return false;
+		if (isset($this->entries[$key]))
+			$this->entries[$key]->merge_with($entry);
+		else
+			$this->entries[$key] = &$entry;
+		return true;
+	}
 
 	/**
 	 * Sets $header PO header to $value
@@ -108,6 +121,15 @@ class Translations {
 			$this->entries[$entry->key()] = $entry;
 		}
 	}
+	
+	function merge_originals_with(&$other) {
+		foreach( $other->entries as $entry ) {
+			if ( !isset( $this->entries[$entry->key()] ) )
+				$this->entries[$entry->key()] = $entry;
+			else
+				$this->entries[$entry->key()]->merge_with($entry);
+		}
+	}
 }
 
 class Gettext_Translations extends Translations {
@@ -126,7 +148,7 @@ class Gettext_Translations extends Translations {
 		}
 		return call_user_func($this->_gettext_select_plural_form, $count);
 	}
-
+	
 	function nplurals_and_expression_from_header($header) {
 		if (preg_match('/^\s*nplurals\s*=\s*(\d+)\s*;\s+plural\s*=\s*(.+)$/', $header, $matches)) {
 			$nplurals = (int)$matches[1];
@@ -152,7 +174,7 @@ class Gettext_Translations extends Translations {
 	/**
 	 * Adds parantheses to the inner parts of ternary operators in
 	 * plural expressions, because PHP evaluates ternary oerators from left to right
-	 *
+	 * 
 	 * @param string $expression the expression without parentheses
 	 * @return string the expression with parentheses added
 	 */
@@ -180,7 +202,7 @@ class Gettext_Translations extends Translations {
 		}
 		return rtrim($res, ';');
 	}
-
+	
 	function make_headers($translation) {
 		$headers = array();
 		// sometimes \ns are used instead of real new lines
@@ -193,7 +215,7 @@ class Gettext_Translations extends Translations {
 		}
 		return $headers;
 	}
-
+	
 	function set_header($header, $value) {
 		parent::set_header($header, $value);
 		if ('Plural-Forms' == $header) {
@@ -212,7 +234,7 @@ if ( !class_exists( 'NOOP_Translations' ) ):
 class NOOP_Translations {
 	var $entries = array();
 	var $headers = array();
-
+	
 	function add_entry($entry) {
 		return true;
 	}