Arpeggio in tablature with two voices.

[AB]

>

Hi List, I'm trying to use connectArpeggios in tablature with no results.
I started with this snippet: http://lsr.dsi.unimi.it/LSR/Snippet?id=294
My "arrangement" for tab is this:

\layout {
 \context {
   \TabStaff
   \consists "Span_arpeggio_engraver"
 }
}

\new TabStaff
 {
 \set Staff.connectArpeggios = ##t
 <<
  {<e' g'>4\arpeggio <d' f'>4 <d' f'>2 }
    \\
  {<d f >2\arpeggio  <g b>2  }
 >>
}

But no arpeggio symbol appears. It's not far from the code I used in Lily
2.11.21 few years ago (example here:
http://img685.imageshack.us/img685/3315/arpeggiooldlily.png) but with Lily
2.14.2 doesn't work.
Thanks in advance.
andy