All reports of missing-pkg-php-tools-buildsystem for the archive. The extended description of this tag is:
The package uses pkg-php-tools but dh command is called without --buildsystem=phppear
pkg-php-tools build system is the recommended tool for building PHP PEAR packages. For more information, install it and read the included README.PEAR.
This tag has not been emitted in any package tested by Lintian.