war:webapp - copying web sources should user preservelastmodified

The war is prepared in a separate directory. The various sources are copied to this directory using the ant copy task. There is an option on this task to preserve the last modified time (preservelastmodified=true). The copy should use this feature.

By not using this feature, we are having a problem with WebLogic not recognizing our precompiled JSP pages. WebLogic looks at the timestamp of the generated JSP classes and the sources, and since they are the same, doesn't use the precompiled classes. The only reason they are the same is that the war:webapp goal does not preserve the last modified information.