Granted, some of the errors that are fatal application errors (i.e. the type that generally only occur when first developing a program, as opposed to things that pop-up at runtime due to environmental issues) get reported directly to the screen.
The error you've got indicates that there is nothing in the EM'TO parameter, i.e. you've haven't specified someone to send the message to.
One bit of confusion with EMAIL protocol that may be responsible for this is that the EM'HEADER also typically contains a "To: so-and-so" clause. But that is more like the addressee info at the top of a letter. It's helpful to the recipient, but no use to the postman since he can only see the address on the outside of the envelope. With the Internet SMTP protocol, the only address that really matters is the one which you pass to EMAILX in the EM'TO parameter.
From the viewpoint of the actual SMTP messages, which you can see in the EMAILX.LOG if you set the LOGLVL (in EMAILX.CFG) high enough, what you pass to EMAILX in the EM'TO parameter actually gets passed to the SMTP service as RCPT TO: ...
28-Feb-07 16:40:57 [EMAIL1-joaquin] > Opening socket mail.pacbell.net (port 25) Flags=1... [Status=0]
28-Feb-07 16:40:57 [EMAIL1-joaquin] [Socket=5856]
28-Feb-07 16:40:57 [EMAIL1-joaquin] > Checking for data... [Status=1]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Read (flags=0)... [Status=102]
28-Feb-07 16:40:58 [EMAIL1-joaquin] < 220 nlpi001.sbcis.sbc.com ESMTP Sendmail 8.13.8 out.dk.spool/8.13.8; Wed, 28 Feb 2007 18:40:01 -0600
28-Feb-07 16:40:58 [EMAIL1-joaquin] > HELO microsabio.com [Status=21]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=1]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Read (flags=0)... [Status=114]
28-Feb-07 16:40:58 [EMAIL1-joaquin] < 250 nlpi001.sbcis.sbc.com Hello adsl-63-199-106-102.dsl.lsan03.pacbell.net [63.199.106.102], pleased to meet you
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=0]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > MAIL FROM: <return@microsabio.com> [Status=36]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=1]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Read (flags=0)... [Status=48]
28-Feb-07 16:40:58 [EMAIL1-joaquin] < 250 2.1.0 <return@microsabio.com>... Sender ok
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=0]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > RCPT TO: <jack@microsabio.com> [Status=32]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=1]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Read (flags=0)... [Status=49]
28-Feb-07 16:40:58 [EMAIL1-joaquin] < 250 2.1.5 <jack@microsabio.com>... Recipient ok
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=0]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > DATA [Status=6]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=1]
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Read (flags=0)... [Status=50]
28-Feb-07 16:40:58 [EMAIL1-joaquin] < 354 Enter mail, end with "." on a line by itself
28-Feb-07 16:40:58 [EMAIL1-joaquin] > Checking for data... [Status=0]
To: jack mcgregor
Re: test
Reply-To: <replyto@microsabio.com>
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