openvrml-gtkplug's install-info invocations are not failsafe against excludedocs
or read-only-netsharedpath-/usr/share installations; appending "|| :" to the
invocations in %post and %preun would fix it.

"Requires(post): /sbin/install-info" and "Requires(preun): /sbin/install-info"
seem to be missing too.

Additionally, on a cosmetic note, install-info works on plain *.info too, no
need to explicitly specify the .gz extension.

More info: http://fedoraproject.org/wiki/Packaging/ScriptletSnippets