fop block padding problem

Just new to xsl-fo I tried something like

<fo:block padding-start="18pt">text</fo:block>

and it does not indent the block when rendering with pdf output.

Everything is fine by directing cocoon to do html output.

I stripped the cocoon complexity off to demonstrate that this seems to be
a fop/pdf problem.

What am I doing wrong here?

You can watch all the details at
http://genschma.de/cocoon/problems/blockIndentProblem.htm

Thanks for any help

Rolf