especially through SMTP (where these values are exposed via the Originator-info
header field): SENDERUSERID, SENDERSERVER, and SERVERTIME.

smb_hashsourcetype().

Overhauled the hfield creation functions to allow insertion (prepending) of
header fields instead of always appending to the existing list fo fields (this
is necessary for the mail server to *insert* Received header fields as required
by RFC2821).
Upped the SMBLIB version 2.51.

1. Wasn't detecting FTN addresses correctly (would return NET_INTERNET, always)
2. Wouldn't detect name@<ip_address> as an Internet address (NET_UNKNOWN)

"OtherHeader" (since not all the headers are actually RFC822-conformant).

Added support for FORWARDED header field to smb_hfieldtype().
Better thread-safety for smb_zonestr() and smb_faddrtoa().

to be RFC-822 (or RFC-977) compliant.
Added smb_netaddrstr() for a thread-safe version of smb_netaddr().

portion of the e-mail address (e.g. "sysop@ 1:103/705", if included).

Created convenience macro: smb_hfield_bin().

(e.g. "user@addr") into an SMB net_type (or NET_NONE for local e-mail).

MSGID's and FTN MSGID's) so that a bit-mask may be passed to functions like
smb_findhash(), allowing selective duplicate searches without pre-marking
hashes (to be skipped) in a message's hash list. This limits the number of
possible hash sources to 32 total (down from 256) - not a real concern.

This change will render existing msg-id's in hash files obsolete.

The usage of the following functions were effected:
smb_addmsg() - from BOOL (dupechk) to bit-field (dupechk_hashes)
smb_msghashes() - removed dupechk kludge (to pre-mark text hash)
smb_findhash() - added source_mask argument to select which source types

source, not the source string itself.
Created smb_hashsource(), which returns the actual source string (if possible).

and allow for selective linking of objects from library archives.