[NMLUG] e-mail and digital ID's (signing and encrypting)

[Ed at Heron-ent.com (Ed Heron)]

  I've got a co-worker who is being asked to encrypt their e-mail to a
vendor.  I've been blissfully ignorant up to this point, but apparently I
need to change this happy state.

  We've got a certificate for our domain.  We should be able to produce
individual 'digital ID's for employees.  I realize this doesn't make
additional money for the CA's, but we'll leave the philosophy out of it for
the moment, ok?  If we were to pay for digital ID's for all employees, at
$20/year/employee, it could quickly get out of control.  I'm not going to
get approval to spend $1600/year on it.  I can barely get approval for $500
for a multiple server certificate for our web farm.

  Can I produce digital ID's for employee's using our domain certificate or
even create a self signed company cert that I could then create employee
certs for use with outlook express and other e-mail programs?

  Can someone provide a URL to a useable how-to?