How to create custom line styles in Writer?

Hello.
In the Line section of the Borders dialog window I can choose one of predefined line styles. How can I set up custom line styles? I use LibreOffice 3.3.4.

To the best of my knowledge you cannot.

What kind of lines do you need? Consider a bug report to post an enhancement request under https://www.libreoffice.org/get-help/bug/