1. to install the ant-contrib
you have to put the ant-contrib.jar to ${ANT_HOME}/lib
2. to apply the ant-contrib, you have to import it first
put following in the tag
3. usually execute ant with following commands:
@echo off
set ANT_HOME=D:\eclipse\plugins\org.apache.ant_1.7.1.v20090120-1145
call “%ANT_HOME%\bin\ant.bat” -f buildModules.xml
Final. a simple solution is to install winant.