UID FETCH misses message if first UID does not exist

Attached is a test mail file with two messages with UIDs 3 and 4.

If I say UID FETCH 1:* ... or UID FETCH 2:* ..., I get only message 3.
If I say UID FETCH 3:*, I get both 3 and 4.  It's the same if I use 5
or 6 instead of *.

% /usr/local/sbin/imap4d --set .tls-mode=ondemand
* OK IMAP4rev1 Test mode
A001 LOGIN "kdo" "..."
A001 OK LOGIN Completed
A002 SELECT "test-inbox"
* 2 EXISTS
* 0 RECENT
* OK [UIDVALIDITY 1599253967] UID valididy status
* OK [UIDNEXT 5] Predicted next uid
* FLAGS (\Answered \Flagged \Deleted \Seen \Draft)
* OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft)] Permanent flags
A002 OK [READ-WRITE] SELECT Completed
A003 UID FETCH 1:* (BODY.PEEK[HEADER.FIELDS (To Cc From Subject)])
* 1 FETCH (UID 3 BODY[HEADER.FIELDS (To Cc From Subject)] {79}
To: <[email protected]>
Subject: first test
From: "Ken Olum,,," <[email protected]>

)
A003 OK UID FETCH Completed