Collision between bar number and rehearsal mark

[Henning Plumeyer]

Hi there,
two weeks ago I found LilyPond and already came across some hurdles.
But now I don't find an answer in the docs for my problem:
How can I avoid the collision between the bar number and the rehearsal mark
in the following example:

%%%%%%%% snippet %%%%%%%%%%%%%%%%%
\version "2.10.10"
\paper{ ragged-right=##t }
\relative c'{
	% next two lines after this comment found in  
bar-number-every-five-reset.ly
        % on the page http://lilypond.org/doc/v2.10/input/test/collated-files
        % I want bar numbers every 5 bars, for demo, I chose every 2 bars here
        \override Score.BarNumber #'break-visibility = #end-of-line-invisible
        \context Score \applyContext #(set-bar-number-visibility 2)
        c1 c \mark #1 c
}
%%%%%%%% end snippet %%%%%%%%%%%%%

Hope it's possible to move the rehearsal mark only in case of collision,  
not all
rehearsal marks.

Greetings
        Henning

DemoMark.png
Description: PNG image