Original of these files can be found in ftp://ftp.cs.berkeley.edu/pub/sendmail;type=d , and copies can be found in ftp://ftp.kyoto.wide.ad.jp/mail/sendmail;type=d . But you may be able to get copys from near anonymous ftp server. Please get from the nearest server which can be obtained by archie service.
2.6W supplies the following features: