dac has already endowed the compiler witht he ability to compile .java files located in a .zip file, without having to unzip them first. (The resulting .class files are stuck in the target directory.)

If the compiler put the compiled .class files into another .zip archive file, this would alleviate many of the filename-length problems that occur on some platforms. The elaborate filename munging tools that are currently used would no longer be necessary if the long filenames never needed to be written to disk, but were stored/compiled within zip files.