Ah, I see. These things are included by default in the XFaces resource
file which is supposed to be installed when you install XFaces; from
that file:
XFaces.mail.annotation1: user
XFaces.mail.annotation2: count
XFaces.mail.unknownAnnotation1: user
XFaces.mail.unknownAnnotation2: count
so the original questioner's installation of xfaces probably didn't work
completely, and the XFaces resource file didn't get into
/usr/lib/X11/app-defaults.