Not all MTAs are as RFC822-compliant as
Occasionally, headers appear that were legal under the
defunct RFC733. The
for example, used to be a comma-separated list of addresses under RFC733
and may cause problems. Note also that
RFC733 date and time syntax differs from that of RFC822 and RFC1123.
Prior to V8
part of a header definition was missing (the
was followed by a colon), a header whose name is the character value
zero was silently accepted and wrongly propagated.
Prior to V8
long header lines in messages (such as
recipients listed) could cause the internal buffer used by
to overflow. The size of that buffer was defined in
as MAXLINE and was 1024 characters. The IDA version defined it as
2048 characters. V8
dynamically allocates memory
and so can handle headers of any size.
When generating an
checks for the absence of only the
H_RCPT flag (see
is ignored. V8.7
will produce an
header only if the
option is set to
Prior to V8.7
program's handling of unbalanced special
characters could lead to an explosion of error mail. Instead of
simply bouncing the offending mail message, it both
returned an error message and forwarded the message to the recipient.
If the message was being exploded through a series of mailing lists,
the error messages continued to increase, possibly drowning
the original site with mail.
Precedence values are stored in integer variables, so care should be
exercised on 2 byte integer machines to avoid having priorities
Macros are not expanded in the
That is, expressions such as
do not have the desired
effect. The literal text
is wrongly listed as the name
or the value.