I use fo structs as following below to descibe articels of an hypertext glossar.
The glossar entries are linked with <fo:basic-link>. The resulting PDF-File is 
3.5 MB huge and has thousands of links. But unfortunately some of them are wrong 
in the PDF while the fo-syntax seems to be correct. There are no error messages 
during generation.

When you analyse the PDF-file with Acrobat there seem to be two types of linking 
errors.

Type 1)
The word where the link should be on is marked blue but the link rectangle is 
placed on a different location. May be this has to do with the 
keep-with-next="always". I think this because when there are a view links in one 
block the rectangles have all the same offset (all on the page before but the 
word are on the next page).

Type 2)
The rectangle of the link is in place over the blue marked word but the link has 
no target.

I can provide the source code of the glossar to reproduce it but I can't publish 
it to public. So please contact me per email to get it.

<fo:table table-layout="fixed" width="100%">
<fo:table-column column-width="proportional-column-width(1)"/>
<fo:table-body><fo:table-row keep-with-next="always"> <fo:table-cell>
<fo:block id = "ipcp"
font-size="12pt"
  font-weight="bold"
  space-before.optimum="12pt"
  space-after.optimum="6pt">
IPCP
</fo:block>
<fo:block><fo:marker marker-class-name="t">IPCP</fo:marker></fo:block>
</fo:table-cell> </fo:table-row>
<fo:table-row keep-with-next="always"> <fo:table-cell>
<fo:block space-after.optimum="6pt"></fo:block>
<fo:block>Internet Protocol Control Protocol&#160;</fo:block>
<fo:block space-after.optimum="6pt"></fo:block>
<fo:block><fo:basic-link color="blue" internal-destination="ncp">Network Control 
Protocol</fo:basic-link> f&#252;r <fo:basic-link color="blue" 
internal-destination="tcp_ip">IP</fo:basic-link>-Verbindungen &#252;ber 
<fo:basic-link color="blue" 
internal-destination="ppp">PPP</fo:basic-link>.&#160;Definiert im <fo:basic-link 
color="blue" internal-destination="rfc">RFC</fo:basic-link> 
1332.&#160;</fo:block>
</fo:table-cell> </fo:table-row> </fo:table-body> </fo:table>