java.time.format.DateTimeFormatter.RFC_1123_DATE_TIME fails to parse time zone names

Question

I'm trying to parse timestamps from a data source that is defined as using RFC1123-compatible date time specifications. My code is:

value = Instant.from (DateTimeFormatter.RFC_1123_DATE_TIME.parse (textValue));

This works fine for some data, but I get exceptions for strings that contain zone names, even ones that are defined in RFC2822 (which is indirectly referenced from RFC1123 because it obsoletes RFC822). Examples:

java.time.format.DateTimeParseException: Text 'Sun, 20 Aug 2017 00:30:00 UT' could not be parsed at index 26
java.time.format.DateTimeParseException: Text 'Mon, 21 Aug 2017 15:00:00 EST' could not be parsed at index 26

How do I persuade DateTimeFormatter to accept this type of date?