Another possible suggestion as to why the initial renameTo failed is if the maven tooling was creating archive deployments (instead of unzipped deployments) then C:\jboss-6.0.0.20101110-CR1\server\default\deploy\mysite.war is actually a zip file, and I clearly cannot copy a .class file into what the tooling is expecting is an exploded folder, but which actually has a zip file somewhere in the path.