Index: main/core/src/main/java/hudson/tasks/MailSender.java
===================================================================
--- main/core/src/main/java/hudson/tasks/MailSender.java	(リビジョン 24903)
+++ main/core/src/main/java/hudson/tasks/MailSender.java	(作業コピー)
@@ -158,7 +158,7 @@
         msg.setSubject(getSubject(build, "Hudson build is back to " + subject + ": "),"UTF-8");
         StringBuffer buf = new StringBuffer();
         appendBuildUrl(build, buf);
-        msg.setText(buf.toString());
+        msg.setText(buf.toString(),"UTF-8");
 
         return msg;
     }
@@ -179,7 +179,7 @@
         msg.setSubject(getSubject(build, subject),"UTF-8");
         StringBuffer buf = new StringBuffer();
         appendBuildUrl(build, buf);
-        msg.setText(buf.toString());
+        msg.setText(buf.toString(),"UTF-8");
 
         return msg;
     }
@@ -272,7 +272,7 @@
             buf.append("Failed to access build log\n\n").append(Functions.printThrowable(e));
         }
 
-        msg.setText(buf.toString());
+        msg.setText(buf.toString(),"UTF-8");
 
         return msg;
     }