Having content sources in different languages in one search collection in WebSphere Portal

Can you have content sources in different languages in one search collection in WebSphere Portal?

When you create a search collection, you can select the language for which the collection is optimized. The index uses this language to analyze the documents when indexing if no other language is specified for the document. This feature enhances the quality of search results for users, because it allows them to use spelling variants, including plurals and inflections, for the search keyword. Portal search uses this language for indexing if there is no language defined for the document.

It is a best practice to use one language per search collection. This practice is applicable for all kinds of content including Portal sites, Web Content Management sites, and regular Web sites.

For WebSphere Portal site crawls only
When crawling and searching a multilingual WebSphere Portal site, however, you may create a single search collection with multiple Portal site content sources in different languages for a solution with lower administration overhead and performance impact.

When you create that collection, select language setting Unspecified case 5. This combines all language specific content sources under that single search collection. However, because the search collection is not optimized for any one particular language, there is potential for less relevant search results.