Most likely, you were following the XOWiki documentation
http://media.wu-wien.ac.at/download/xowiki-doc/#xowiki-object which suggests to name the object "de:cgi".
"de" is the language prefix (see http://alice.wu-wien.ac.at:8000/xowiki-doc/#intra-wiki-links)
language prefixes are used to provide content in multiple languages. If in a page reference a language prefix is omitted, it is completed from a default (either from the referring page, or the language locale of the browser, depending on a configuration flag). In any case, one can use the name with the explicit language prefix.
