How do you tell Lilypond not to jump strings when sliding?

[Jay Vara]

> I'm not top posting.

When you give lilypond a piece of music, it automatically generates the 
music and guitar tabs for it. When there are glissandos in the music, 
lilypod does show the slides automatically.

However, many times, it shows slides from one string to another, rather 
than choosing frets on the same string. Is there a way to force it to 
restrict slides to a single string?

The following code shows an example. The second measure shows the 
automatically generated lilypod slides that go from the first string to 
the second string. (This can not be played) In the third measure, I have 
manually forced the notes to all be on the second string. I need a way 
to do this automatically.
Also, I tried to avoid open strings by setting restrainOpenStrings to 
true. It does not seem to work.

\version "2.18.2"

musica = \relative c' {e2 e}
musicb = \relative c' {e2 e8\glissando (d16\glissando e16)}
musicc = \relative c' {e2 e8\2\glissando (d16\glissando e16\2)}

\score { \new StaffGroup 
         
         <<
           \new Staff {\musica \musicb \musicc}
           \new TabStaff {
                       \set TabStaff.restrainOpenStrings = ##t
                       \tabFullNotation
                       \musica \musicb \musicc}
         >>
}