collision between glissando and sharp

[chip]

In the following code sample how would I prevent the glissando and sharp 
sign collision?
--
Thanks,
Chip


\version "2.12.1"
\header {}
staffNotes = \new Staff  {
   \time 4/4
   \key c \major
   \clef treble
   \relative c'' {
 \override Glissando #'thickness = #3
 \override Glissando #'style = #'zigzag
 \override Glissando #'minimum-length = #6
 \override Glissando #'springs-and-rods = #ly:spanner::set-spacing-rods
 c2 a\glissando cis d }}
\score { << \staffNotes >>
   \midi {}
   \layout  {}}
\paper {}