All reports of usr-share-doc-symlink-to-foreign-package for the archive. The extended description of this tag is:
If the package installs a symbolic link /usr/share/doc/pkg1 -> pkg2, then pkg1 and pkg2 must both come from the same source package.
The best solution is probably to stop symlinking the /usr/share/doc directory for this package and instead include a real /usr/share/doc/pkg1 directory within pkg1 with the appropriate contents (such as the copyright and changelog.Debian.gz files).
Refer to Debian Policy Manual section 12.5 (Copyright information) for details.
This tag has not been emitted in any package tested by Lintian.