If you intend editing PhotoML files using (x)emacs, remember
to set the SGML_SEARCH_PATH environment variable in your
shell configuration file. Assuming this variable is
currently not set in your environment, for csh/tcsh use
    setenv SGML_SEARCH_PATH /usr/share/photoml/dtd
or for sh/bash use:
    SGML_SEARCH_PATH=/usr/share/photoml/dtd; export SGML_SEARCH_PATH

Thanks to Cesare Tirabassi for assistance with cleaning up the Ubuntu
Debianization of this package.
