The LinkedIn API uses XML with node names that contain dashes (-). HttpClientXMLFormatter replaces the dashes with underscores in the function sanitizeNodeName() (line 69 in HttpClientXMLFormatter.inc).

According to the standard, dashes are allowed:
"Tag names cannot contain any of the characters !"#$%&'()*+,/;<=>?@[\]^`{|}~, nor a space character, and cannot start with -, ., or a numeric digit."

Can this be fixed with a proper preg_replace?