I'm not sure what CMS gdnet uses so this might just be a limitation of the software.
It would be real nice if you could edit your post for up to 5 minutes or until the first reply appears without getting that ugly little "Edited by boolean, Today, 07:39 PM." at the bottom. Half the time I'm just going back to add a period or fix a small typo. I think the old version of the site allowed this which might be why I got used to it.
Small thing, just a suggestion