tie misplaced on staff change

[Peter Dixon]

I am using Lilypond 1.6.4 on Cygwin and ly2dvi -P.  The code below compiles
perfectly but the second tie is placed horizontally near the bottom of the
lower staff instead of joining the 2 notes.

Any suggestions?

Peter Dixon
--------------------------------------------------------
\score {
    \context PianoStaff <
 \context Staff = upper \notes \relative c'
 { \time 3/4
   \key f \major
   \stemDown c2. ~ c2. ~ \stemUp
   \translator Staff=lower c2. ~ c2 \translator Staff=upper d4
      }
 \context Staff = lower \notes {
     \clef bass \key f \major \stemDown c2. c c c
 }
    >
    \paper {}
}
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