gap property on glissandi not working in 2.11

[Steven de Rooij]

I'm new to Lilypond, so please bear with me if I'm pointing out the obvious. I
tried to solve a glissando collision with a dotted half-note by modifying its
gap property, but found that this does not work in lilypond 2.11. This can be
observed in the example in the manual, where a glissando is modified using

\override Glissando #'gap = #0.1

... to make it more clearly visible. In the 2.10 manual, this works. In the 2.11
manual, the glissando is not shortened.

Cheers,

Steven