Empty requestors in RT 3.4.1


I have installed RT 3.4.1 with Oracle db. When I create new ticket by
writing the mail, the field Requestors is empty. Also, when I try to
reply to this ticket, i have errors in my log:

#500018/50097 - Script 2 (/opt/rt3/lib/RT/Action/SendEmail.pm:235)
No recipients found. Not sending. (/opt/rt3/lib/RT/Action/SendEmail.pm:247)
#50018/50097 - Scrip 3 (/opt/rt3/lib/RT/Action/SendEmail.pm:235)
Could not send mail. (/opt/rt3/lib/RT/Action/SendEmail.pm:280)

In the table Users, the field EmailAddress is filled for person, who has
made this ticket.

Configuration: RT 3.4.1, Perl 5.8.6, Apache 2.0.53, fastcgi, postfix,
Oracle 9i, SuSE 9.2

Does anyone use RT3 with Oracle?

Thanks for any advice.

David Stepan