Redmine

Hi Folks;

I have installed Redmine my Virtual Ubuntu machine by following http://www.redmine.org/wiki/redmine/HowTo_Install_Redmine_in_Ubuntu document very well. It is top down approach to install Redmine almost an hour. But I have an to much delay while sending mail with sendmail as you can see from the output of webrick command line:

=============================================================================================================
Processing SettingsController#edit (for 10.30.50.13 at 2009-11-06 18:31:00) [GET]
Session ID: 2a7c3bf3a3f13d10d81586cdf6558861
Parameters: {"action"=>"edit", "controller"=>"settings", "tab"=>"notifications"}
Rendering template within layouts/base
Rendering settings/edit
Completed in 0.53992 (1 reqs/sec) | Rendering: 0.47475 (87%) | DB: 0.05173 (9%) | 200 OK [http://10.30.50.60/settings/edit?tab=notifications] =============================================================================================================

And my system is:
About your application's environment
Ruby version 1.8.7 (i486-linux)
RubyGems version 1.3.5
Rails version 2.1.2
Active Record version 2.1.2
Action Pack version 2.1.2
Active Resource version 2.1.2
Action Mailer version 2.1.2
Active Support version 2.1.2
Edge Rails revision unknown
Application root /opt/redmine/redmine-0.8.6
Environment development
Database adapter mysql

Is there anyone who can guess the problem? I am strongly suspect about sendmail. Because I always have to wait one minute to issue a bug, while mail support is active. If I remove mail support everything working normal.
Thanks in advance.

-Umit Uzun