Mail read or not?

We are using 'Sun Java System Messenger Express 6.2'. For administrators, is there any way to know if the mail recipients opened their email or not?Thanks in advance,GJ
[198 byte] By [gulzarjaggia] at [2007-11-27 6:45:26]
# 1
It's non-trivial.You can use the "proxyauth" extension via imap, or with a webmail url like this one: http://your.domain/login.msc?user=admin&password=password&fmt-out=text/ html&proxyauth=the_user
jay_plesseta at 2007-7-12 18:17:16 > top of Java-index,E-Mail, Calendar, & Collaboration,Sun Java System Messaging Server...