Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 4813)
+++ wp-includes/functions.php	(working copy)
@@ -80,6 +80,14 @@
 	return $j;
 }
 
+function number_format_i18n($number, $decimals = null) {
+	global $wp_locale;
+	// let the user override the precision only
+	$decimals = is_null($decimals)? $wp_locale->number_format['decimals'] : intval($decimals);
+
+	return number_format($number, $decimals, $wp_locale->number_format['decimal_point'], $wp_locale->number_format['thousands_sep']);
+}
+
 function get_weekstartend($mysqlstring, $start_of_week) {
 	$my = substr($mysqlstring,0,4);
 	$mm = substr($mysqlstring,8,2);
Index: wp-includes/locale.php
===================================================================
--- wp-includes/locale.php	(revision 4813)
+++ wp-includes/locale.php	(working copy)
@@ -87,6 +87,18 @@
 		$this->meridiem['AM'] = __('AM');
 		$this->meridiem['PM'] = __('PM');
 
+		// Numbers formatting
+		// See http://php.net/number_format
+
+		$trans = __('number_format_decimals'); 
+		$this->number_format['decimals'] = ('number_format_decimals' == $trans) ? 0 : $trans;
+		
+		$trans = __('number_format_decimal_point');
+		$this->number_format['decimal_point'] = ('number_format_decimal_point' == $trans) ? '.' : $trans;
+
+		$trans = __('number_format_thousands_sep');	
+		$this->number_format['thousands_sep'] = ('number_format_thousands_sep' == $trans) ? ',' : $trans; 
+		
 		// Import global locale vars set during inclusion of $locale.php.
 		foreach ( $this->locale_vars as $var ) {
 			if ( isset($GLOBALS[$var]) )
@@ -138,4 +150,4 @@
 	}
 }
 
-?>
\ No newline at end of file
+?>