Both name are identical Did you enter & # followed by a number, which was converted to a « ' » ?
If yes, that's probably because in the XML some special characters are stored like that, but I do not see why this would be a bug...
Try to put a space after the "&" so it is not converted (to check that it is the normal code of the « ' »)
Maybe it is a problem of the PHP application then As far as I know the XML file generated by AMC is valid.