Hola,
leyendo un post en xda sobre el programa s2u2 he visto esto:
Reset Unread Count
If your device has suspicious unknown count of any unread email/vmail/sms/mms, use this file (
ResetUnreadCount.cab) to reset them.
Os pongo la url del hilo por si le quereis echar un vistazo
http://forum.xda-developers.com/showthread.php?t=527523