We have configured jenkins to automatically install the jdk and maven on our build nodes, using the option "Extract .zip/.tar.gz". There we provide packaged zip files for each tool, make them available via http and configure the link to the tool in the installer - standard setup.

The issue we are seeing however is that jenkins does not detect updates for a package, contrary to what it says in the help item for "Download URL for binary archive":

URL from which to download the tool in binary form. Should be either a ZIP or a GZip-compressed TAR file. The timestamp on the server will be compared to the local version (if any) so you can publish updates easily. The URL must be accessible from the Jenkins master but need not be accessible from slaves.

Our jenkins master is solaris, the build nodes are windows. They are all timesync'ed.

I noticed that the .timestamp files jenkins generates in each tool directory is 01/01/1970 , this seems off a bit no, any ideas ?