To overcome this, I wanted to have something better.
My wife just thrown away this as the holder at the end was broken:
I decided to cut it into the desired length and design a holder for it, what fits onto the top of the printer.
The printer hase 4 holes at each side, I don't know why - no it is not he holes for the bowden extruder, different holes what I talk about.
So I designed a plastic part as the holder (two identical required), and printed.
Here is the result:
It is available on Thingiverse: http://www.thingiverse.com/thing:2235889