Cannot find javahl, svnkit nor command line svn client

I've done numerous svn / ant set-ups and but this time cann't figure out what's wrong.

Using Linux,

svn 1.6.6
ant 1.8.2
svnant 1.3.1

I've copied the svnant jar files into $ANT_HOME/lib

top@secret:~/apps/apache-ant-1.8.2/lib$ ls -l
-rw-r--r-- 1 root root  244831 2011-06-23 07:55 ganymed.jar
-rw-r--r-- 1 root root  948100 2011-06-23 07:55 jna.jar
-rw-r--r-- 1 root root   76383 2011-06-23 07:55 svnant.jar
-rw-r--r-- 1 root root  215757 2011-06-23 07:55 svnClientAdapter.jar
-rw-r--r-- 1 root root   89412 2011-06-23 07:55 svnjavahl.jar

etc...

My build file specifies:

<taskdef name="svn" classname="org.tigris.subversion.svnant.SvnTask"   />

But whenever I execute

   <target name="update">
                <svn>
                        <update dir="."/>
                </svn>
        </target>

I get the dreaded:

update:
      [svn] Missing 'javahl' dependencies on the classpath !

BUILD FAILED
/home/top/apps/utils/build.xml:26: Cannot find javahl, svnkit nor command line svn client

Any ideas what I'm doing wrong?

I assumed copying the svnant jars into $ANT_HOME/lib should be enough?