The XML specification explicitly states that no whitespace is allowed in element names (while MySQL allows for whitespace in database, table and column names), as seen here:
http://www.w3schools.com/XML/xml_elements.asp
Virtually all XML parsers use whitespace characters in XML element to differentiate between the elements name and any attributes that is possesses. A name with whitespace interferes with this and disrupts all XML parsers that behave in this way.
Forgot to mention that my solution to this problem was to replace whitespace in database, table, and column names with underscores (a "_").
Thanks, merged for 3.1.5. I changed the title because "whitespace" means more characters than just spaces.