Centering lines of text in FO output

Hi
I have a problem which looks like it ought be general.  there may be 
an easy way around it, but I haven't found it.

Within some normal <para> text I want to center a group of lines in a 
PDF file, e.g. I want to get output like:

  This is a normal line of text from a <para> and
  </para> piece of XML
                    abc def
              qwerty asdfgh zxcvbn
                      123
                qazwsx edc rfvt
  This is a normal line of text from a <para> and
  </para> piece of XML

I've tried using a single column table with line height control - it 
works, but it's a very inelegant solution, and very slow with all the 
PIs.

A better solution would be to use a <simplelist columns="1" 
type="vert"> with each line a <member>, but how to center the lines?

Am I missing something simple?  I'm using XEP.

Ron
-- 
Ron Catterall, Phd, DSc			        	email: 

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