Background-image question

Hello,
I am interested in getting an update on using background-image in FOP.
I have tried background-image in the latest FOP release 0.20.1 but it
doesn't seem to work. On the FOP Apache websites I have checked the
Limitations and Features pages but do not see anything.
What is the issue with background images? Is it a PDF thing?
 
In my XSL I tried this:

    <fo:block background-image="file:elipse.gif">
      <xsl:text>IMAGE TEXT</xsl:text>
    </fo:block>

This is what my log said:

Error in background-image property value 'file:elipse.gif':
org.apache.fop.fo.expr.PropertyException: illegal character

In my PDF all that comes out is "IMAGE TEXT" but no image.

What am I doing wrong?

Also if anyone can give me an idea of when this functionality would be
available I would appreciate it!
Thanks,
Erich Kilmer
Bell+Howell