after-title-space being ignored

[Alberto Simões]

Hello

I am trying to use after-title-space variable to get some extra space
between the 'meter' line and the 'lyrics' line that is appearing in the
top of the stave.

I tried to put

\paper {
    after-title-space = 3\cm
}

but nothing changed.

Also, I tried to put that same line in the \layout section but nothing
happens as well.

Can anybody give me an hint on why this does not work or how can I force
that extra space?

Thank you in advance,
Alberto

-- 
Alberto Simões