consecutive \repeat volta: bug?

[luis jure]

this looks like a bug to me, but i'd like to hear comments from people with
a better understanding of lilypond than me.

when writing two consecutive "\repeat volta", the thin bar lines are
omitted, which i think is wrong. in any case, it's usual to use only one
thick line (here they are repeated).

here's some basic code, and the results using 2.16.0

  \relative c'' {
        c1
        \repeat volta 3 { c2 c } |
        \repeat volta 3 { c2 c } |
}

repeats.png
Description: PNG image