When trying to add an URL alias to a node (content/urlalias/) where an URL alias already exists in another language, the following error message is produced:

The URL alias <</path/to/node>> already exists, and it points to <<content/view/full/424242>>

This is not a problem for generated aliases (those that are made automatically based on the name of the object). If the objects name is the same in several languages, the url will also be the same. It is inconsistent that you can't do this with custom url aliases.

The patch allows you to have custom url aliases with the same name, provided that the languages are different.

NB: The patch is only tested on ezp 4.0, and only minimally at that. Do not use in production!

Steps to reproduce

0. Have a site with at least two languges configured.
1. Go to a node in admin, in the context menu choose "Manage URL aliases", get redirected to /content/urlalias/<node_id>
2. Enter a name in "URL alias name", select a language, uncheck "Alias should redirect to its destination" and click "Create".
3. Repeat step 2 with the same name but a different language. Get the error message:
The URL alias <</path/to/node>> already exists, and it points to <<content/view/full/424242>>