Currently, we force the i18n values from XSL to be i18n keys. As the standard implementation (https://cocoon.apache.org/2.1/userdocs/i18nTransformer.html#Translation+with+param+substitution) we should accept static messages too.

For example, this code:

<i18n:translate>
    <i18n:text>My lovely text: \{myText}</i18n:text>
    <i18n:param name="myText">It's so nice!</i18n:param>
</i18n:translate>

Display this:

null:My lovely text: It's so nice!

(null can be a real catalog depending of the context)

Also, note that the i18n:text value between tags is the default value, not the key (https://cocoon.apache.org/2.1/userdocs/i18nTransformer.html#i18n%3Atext).

In our case, we force the default value to be a key.
Only the key should be a key, not the default value.