I've found, using kdepim-3.0.2-3, that I can create todo items in korganizer,
but afterwards, am unable to edit them. This seems, too, to be a problem with
kde as distributed with RedHat 7.3:
Later version(s) of kde fix this, and I can confirm it works as of 3.0.5.
it's fixed in 3.1 or 3.0.5a, which will be released as errata soon.