Macromedia Product Security Bulletin (MPSB01-03) : JRun 3.1, 3.0, 2.3.3: Patch available for ability to view jsp source code when Ending an URL with js%70 Instead of JSP
It is possible to view the JSP source code when accessing a JSP via the URL as "js%70". Depending on the version of JRun, the source code is visible either in the browser or by doing a "View Source" on the displayed page.
Macromedia Product Security Bulletin (MPSB01-03)