Technical Notes

Installing PreciseMail In A Solaris Zone - 12/7/05
Installing & Configuring Open LDAP - 9/30/05
Dealing with unsolicited bulk e-mail
Shield your clients from buffer overruns
General Virus Info
Virus scanning and related issues
PMDF 101: A message's trip through PMDF
Routing mail to other local mail systems
POP, IMAP, Pine and ACAP
Document & format conversion and encryption
Generating vacation notices
Sieve Internet Drafts
PMDF-LAN and related issues
PMDF-MR, PMDF-X400 and related issues

Below are some discussions about e-mail which may prove of interest to you.

Postmaster responsibilities
The meaning of text/plain. A discussion of text messages that expect the receiving user agent to wrap long lines of text.
Comments by Joel Snyder about firewall products
General security comments and SMTP firewall security in detail
Comments on sendmail