It looks like the xowikI::Package init method is not called.
If ound after modifying the code like this
::xowiki::Package initialize \
-package_id $package_id -user_id $user_id \
-parameter $parameter -init_url false -actual_query ""
array set site_node [site_node::get_from_object_id -object_id $package_id]
::$package_id set_url -url $site_node(url)
that the folder_id attribute for the xowiki::Package was not set
so I added it like this:
::xowiki::Package initialize \
-package_id $package_id -user_id $user_id \
-parameter $parameter -init_url false -actual_query ""
array set site_node [site_node::get_from_object_id -object_id $package_id]
::$package_id require_folder_object
::$package_id set_url -url $site_node(url)
and now it works.
