ISO8601 with milliseconds in json using Jackson

import com.fasterxml.jackson.databind.util.ISO8601DateFormat;

objectMapper.setDateFormat(new ISO8601DateFormat());

Nice but this ignores milliseconds, how can I get them in the dates without using the non-thread-safe SimpleDateFormatter?

https://github.com/FasterXML/jackson-databind/blob/master/src/main/java/com/fasterxml/jackson/databind/util/ISO8601DateFormat.java