Just a few suggestions. I am not having the problem you mention, but I am using Firefox. What browser are you using? I am also not seeing problems with comments. I am receiving them and have been able to answer them too.

I post with either ScribeFire, which is an add-on to Firefox, or by using Posterous.

With Posterous, you sign up for an account which is free. Then you can post to LiveJournal by sending an email message. That is piped straight through to LJ.

I don't know if I am bypassing the problem, or it is browser related. Let's see if this posts OK. I do read LJ in Firefox, and this comment is posted through Firefox.