Bad or unwanted comments (which are not spam) sometimes causes great problem in a community.
Are there any plugin that help to do comment moderation, for example "Your comment will be visible after approval by a mod" ?

I have seen the Editable Comments plugin - it is sort of generic and seems not allow a system that posts comments after approval / without approval as configured by a blog owner.

In the original Elgg site, an user can edit comments only made by her/him - however the Editable Comments plugin allows the post-owner to edit any comment. What is the plugin that Elgg org is using so that only comment-maker can edit only her/his comment?