Redmine

Already implemented. See again RedmineIssues.
Comments (I presume you mean the issue notes aka journals, in fact the updates of an issue) can be edited when a user's role contains the "Issue tracking - Edit notes" permission.

I am using 0.9.3 and I cannot edit the "Description" field of my issues.

I use the description field to list the task in a bullet list, and often more bullets get added to this list. However, the only way to add bullets is to update the issue with a note.

This is not what I want. I would really like to be able to EDIT the "Description" field, so it is always updated with the current specifications. Otherwise one have to read through all notes added to be sure that all demands are met for the issue at hand.

Please let me know if this is intended?

I am both admin, manager, developer, and reporter...

I think Mischa understood. Please, re-read the link he gave.
It's not obvious I know (see #4900) but it's possible to edit the description by clicking the "More" link at the top of the update form.