#119 empty INTERVAL value in RRULE

[Claude Viéville]

We use ical4j with SOGo server. in RRULE SOGo sends empty INTERVAL rule vale such as INTERVAL=;
ical4j doesnot suport empty interval value during parsing. cf line 207 of Recur.java
else if (INTERVAL.equals(token)) {
interval = Integer.parseInt(nextToken(t, token));
}
where is the error ? on SOGo side or on ical4j side ?