In oracle apex, I am using APEX_MAIL.SEND function to send mail. The mail is sent correctly, however, automatically, another mail arrives with the following information:

Your message WAS SUCCESSFULLY RELAYED to:
  <account@domain.net>

This delivery report was generated by the program amavisd-new at host deneb.catsa.net. Our internal reference code for your message is 35575-18/W5fQAUCbp11y

INVALID HEADER: MISSING REQUIRED HEADER FIELD
Missing required header field: "Date"
Return-Path: <crvictor@catsa.net>
From: crvictor@catsa.net
Message ID: <D6084414148F0763E053020010AC1735@172.16.0.15>
Subject: =?utf-8?B?QXByb2JhY2nDs24gZGUgc29saWNpdHVkICMxNDg1NSBw?=
  =?utf-8?B?b3IgQ1JWSUNUT1I=?=

MISSING REQUIRED HEADER FIELD

The RFC 5322 document specifies rules for forming internet messages. Section '3.6. Field Definitions' specifies that certain header fields are required (origination date field and the "From:" originator field). How can I send the date header using this function? Note: I don't want to use pl/sql's utl_smtp