Overall UNIX build system improvements:
Overall UNIX build system improvements:

* Makefile header is now completely dynamic
* Absolute paths in (top_)?(src|build)dir and VPATH
  (fixes Tru64 support)
* VPATH does not contain variables anymore
  (fixes UnixWare support)


git-svn-id: 4b064e69dc630d28214c1e1442d27300cccf8e9a@23418 c90b9560-bf6c-de11-be94-00142212c4b1

DQNEO/PEAR_Exception