listTableIndexes() return an empty array with doctrine-1.2.2

I've a table A with 3 indexes. I would like to retrieve this list of indexes by using listTableIndexes() but I just get an empty array.

I found the problem into listTableIndexes():
The $keyName and $nonUnique are set in lowercase in my case.
But the result of $indexes = $this->conn->fetchAssoc($query); have field names in both lower/upper case, e.g.:
'Non_unique' => string '1' (length=1)
'Key_name' => string 'module' (length=6)

But maybe that's a config problem from my part and the case of $keyName and $nonUnique should not be modified.