Comment 7 for bug 505400

reproduced with Inkscape 0.47 r22853 on OS X 10.5.8

steps to reproduce:
1) new document
2) pen tool: Spiro mode, Smoothing 50, Shape 'Triangle in'
3) draw curve: drag-click fast or click twice to create a straight short path (without typical spiro splines)
4) select (<space>), duplicate (ctrl+d), move (<shift>+cursor), pen (<space>)
5) repeat 3+4 until crash