hibernate3.1.2,postgresql 7.4.1......

hi, now in process to complete hibernate tutorial..As mentioned early, i'm using postgres database server and put the jdbc driver to /lib folder. I got error when try to run this command: ant run -Daction=store

the error:
[java] 17:40:42,147 FATAL DriverManagerConnectionProvider:65 - JDBC Driver class not found: org.postgresql.Driver
[java] java.lang.ClassNotFoundException: org.postgresql.Driver
[java] at java.net.URLClassLoader$1.run(URLClassLoader.java:199)

i already check my postgres jdbc driver and it the right one..

any help appreciated

the jar file has to be in the classpath, make sure that build.xml includes it when constructs classpath for the java task