2010/8/16 Magnus Manske <magnusmanske@googlemail.com>

Not at all, though
seems to work fine. You can also try {{PAGENAMEE}} (note the two E).

My question was definitely banal. With  {{PAGENAMEE}} the template http://it.wikisource.org/wiki/Template:BackToScroll runs perfectly: see http://it.wikisource.org/wiki/Indice:Rime_%28Vittorelli%29.djvu .
Thanks Magnus (even if some of our it.source users poined my mistake, I appreciated a lot your attention and suggestions!)