I recently upgraded my system from Mint12 to Mint14 and had severe issues with getting my old projects to work nicely on the new system. To summarize it all:
David mentioned using ivy to manage 3rd party dependencies.
This example demonstrates how both the ant-contrib and subversion dependencies can be downloaded and cached by the build.
On the issue of subversion I have always found it problematic to enable within ANT. What I desired was a pure java approach would be more robust and cross platform. My solution was svnkit and then create a macro to call the command-line client.
Demonstrates using ivy to managed subversion and ant-contrib dependencies. Dependencies are declared in-line, using the cachepath task. Use a separate ivy.xml file if you're managing multiple classpaths
Apache Ant(TM) version 1.8.2
Apache Ivy 2.3.0-rc2
Letter @{letter}