No problems with SUM function reproducible with "Ooo 3.1.1 WIN XP DE[OOO310m19
(Build 9420)]" or  "Ooo-Dev 3.3.0 multilingual version German UI WIN XP:
[DEV300m74 (Build 9487)]! I can't understand reporte's problem.

This is not a valid bug report.

@stephen7218:
Pls. feel free to reopen the issue if you find out that the problem still exists
in a current stable version (3.1.1 or later).
Before you file further issues or post again here, please read our guidelines on
<http://qa.openoffice.org/issue_handling/pre_submission.html> and  
<http://www.openoffice.org/bugs/bug_writing_guidelines.html>, then select
correct information for all Issue Tracker selection fields, 
contribute a clear step by step instruction containing all observations (error
messages ...), _every_key_press_and_every_mouse_click_ how to reproduce the
problem, and explain why you believe that your results are unexpected.
That means (for example): 
 do not write something like "I am not able to ...", but
  6. left mouse click on …
     expected: …, color of … changes, … 
     actual: no …., color remains white, no …

Screenshots might help to explain the problem.

Please 
- always specify your OOo version, localization,
  OS and Platform you used for your tests!
- attach a sample document (always with ODF source document)!
- Always contribute a meaningful Summary

I will close the issue within 10 days if we don't get required further information.

invalid -> closed