diff --git a/thunderbird/mailnews/base/content/charsetList.xml b/thunderbird/mailnews/base/content/charsetList.xml
index bff4305..8fd7bac 100644
--- a/thunderbird/mailnews/base/content/charsetList.xml
+++ b/thunderbird/mailnews/base/content/charsetList.xml
@@ -18,7 +18,7 @@
 
         if (this.getAttribute("subset") == "sending")
           charsetValues = ["UTF-8", "EUC-KR", "gbk", "gb18030", "ISO-2022-JP",
-                           "ISO-8859-1", "ISO-8859-7", "windows-1252"];
+                           "ISO-8859-1", "ISO-8859-7", "windows-1251", "windows-1252"];
 
         else if (!this.getAttribute("subset")
                  || this.getAttribute("subset") == "viewing")