[andreamarucci]

I made it!

this is the piece of code

<if condition="$rsvp_yes">
<b>$vbphrase[calendar_rsvpd] $vbphrase[yes]: $rsvp_yes_count </b>
<if condition="$eventinfo[rsvp_max_guests]">
(<phrase 1="$rsvp_yes_members" 2="$rsvp_yes_guests">$vbphrase[x_members_and_y_guests_fc]</phrase>)
</if>
<ul><if condition="$vboptions[rah_rsvp_showavatar]"><table>$rsvp_yes</table><else />$rsvp_yes</if></ul>
</if>
<if condition="$rsvp_maybe">
<b>$vbphrase[calendar_rsvpd] $vbphrase[maybe]: $rsvp_maybe_count</b>
<if condition="$eventinfo[rsvp_max_guests]">
(<phrase 1="$rsvp_maybe_members" 2="$rsvp_maybe_guests">$vbphrase[x_members_and_y_guests_fc]</phrase>)
</if>

and you've to change two instances of x_members_and_y_guests to x_members_and_y_guests_fc