[Inkscape-user] Masking problem

Hi,

I try to use the possibility to mask objects. As I read, the normal way is to select the object to be masked, select a second object above, which will be the mask, then: Object > mask > set. I did this, but as result, the object below just disappears.

Please see the demo at: http://www.hagoschaos.de/test/test.html

What am I doing wrong? Or am I misunderstanding the way this function works? Some help please.

I used a two hours ago downloaded Inkscape 0.44

Regards, Hago