I was trying to update a EAR (jar) file:
[root@localhost somefolder]# ls
bugs packaging-build.xml StockEJB.jar xdoclet-build.xml
index.jsp pages StockWeb.war
META-INF StockEJB-client.jar WEB-INF
[root@localhost somefolder]# jar -uf Stock.ear StockEJB.jar
jar: `-u' mode unimplemented.
What does it mean by "-u mode unimplemented"? Where can I get a jar tool that supports -u option? btw, it's a Fedora box.