Help - build.xml:385: destDir attribute must be present

Hi,

I checked out a working copy of svn slide. When I tried to build it
using the command:

$ant -f build.xml all webapp-dist

I failed. The error messages were as follows. Can anyong please help?

Thanks,
Ben

==================
...
     [copy] Copying 8 files to
C:\fwang\programming\java\eclipse\workspace\slidesvncmd\dist\slide\conf
all:
main:
     [echo] Building Slide Core API
     [echo] Building Slide WebDAV Servlet
     [echo] Building Standard Stores
     [echo] Building Default Roles
     [echo] Building JAAS LoginModule
ojb-xml:
[ojbdoclet] C:\fwang\programming\java\eclipse\workspace\slidesvncmd\build.xml:385:
destDir attribute must be present.
[ojbdoclet] at xdoclet.DocletTask.validateOptions(DocletTask.java:489)
[ojbdoclet] at xjavadoc.ant.XJavadocTask.execute(XJavadocTask.java:94)
...
[ojbdoclet] at org.eclipse.ant.internal.ui.antsupport.InternalAntRunner.main(InternalAntRunner.java:137)

BUILD FAILED
C:\fwang\programming\java\eclipse\workspace\slidesvncmd\build.xml:385:
Unexpected error