Keep-with-previous.within-page causes block to be put

I am creating a pdf (AntennaHouse) containing two columns of text and a
signature at the end. What I want is for the signature to never be placed
alone on a page. To do this I am using keep-with-previous.within-page on the
signature blocks, which sort of solves the problem. The signature stays with
the text, but it doesn't respect the bottom margin. If I don't use
keep-with-previous the flow breaks nicely at the 2,5 cm margin. I have my flow
set to region-body and the margin-bottom is 2,5 cm.

<fo:region-body column-count="2" column-gap="23.34pt" margin-top="7cm"
margin-bottom="2.5cm"/>

Using XMLSpy gives this fo:
<fo:flow flow-name="xsl-region-body" font-size="10pt" text-align="justify"
font-family="Times New Roman" hyphenate="true" language="da" orphans="2"
widows="2" margin-bottom="2,5cm">
<fo:block space-before="0pt" margin-bottom="0pt" text-indent="10pt">my
text</fo:block>
...
<fo:block space-before="0pt" margin-bottom="0pt" text-indent="10pt">my
text</fo:block>
<fo:block margin-top="22pt" margin-bottom="10pt" text-align="center"
font-style="italic" span="all" keep-with-previous.within-page="always"
hyphenate="false">SignatureLocation</fo:block>
<fo:block space-before="10pt" margin-bottom="0pt" text-align="center"
font-variant="small-caps" span="all" keep-with-previous.within-page="always"
hyphenate="false">SignatureName</fo:block>

What I would like to happen is that the signature blocks respects the
bottom-margin of the region-body. So when this situation occurs, instead of
forcing the signature blocks to the margin of the previous page, the page
break is put between the text blocks, leaving me with a second page containing
some text and then the signature.

Thanks in advance...