Please give this notes.ini a try. This is directly from the Domino 6 Admin help:
Syntax: SMTPStrict821LineSyntax=value
Description: Specifies whether the SMTP task requires all protocol text be terminated by CRLF:
0 - 821 standard is not enforced (LF is accepted as a line terminator)
1 - 821 standard is enforced
Applies to: Servers
Default: 0
UI equivalent: None
See Also
SMTPStrict821AddressSyntax
Editing the NOTES.INI file
NOTES.INI Settings