I've been swamped at work the last few weeks, otherwise I would have posted something about this as well. Got some time now, so I was checking the forums to see if this has been brought up yet and possibly make a bug report finally on it.
Yes, I've experienced this, and I know a good many others who have as well.
I also play on G-Land.
My experience is also that the only way to remedy this is to completely disband the party and regroup.
I've also experienced this where one or two members of the party will get isolated via this bug while the rest of the party will have their own working party chat separate from it. In the last few weeks (when I've had time to play) I've encountered it half a dozen times. With my regular friends we notice it right away. Did a PUG Raid a while ago (Temple of the Death Wyrm) and didn't notice it until 2/3rds of the way through (when the choices were red-light-green-light and gravity). That time was one of those times where 2 people were able to type and speak to each other but no one else, while everyone else could talk and type to each other but not to those two. One of those 2 affected was the party leader who had to start communicating via /tells through a liaison. Apparently he was talking and giving instructions the whole time and was just lucky that most everyone was on the same page... but gravity requires some communication to get through, which made it obvious that something was wrong. Almost everyone in the group at that time had experienced this at some point prior to this particular run and thus was very understanding, so we were able to pull through and finish.
When I first experienced this, me and my friends spent nearly an hour trying to trouble shoot it in game (we were playing at a time when there is no in-game support so we had to resolve it ourselves in order to be able to play together). Affected player drops and rejoins: persists. Affected player reboots DDO client: persists. Affected player reboots computer: persists. Part leader changes who is leader then re-invited affected player: persists. As already mentioned, the only way we've found to fix this issue is for everyone to disband and reform a brand new party from scratch. Unbelievably frustrating.
I'm now actually hoping that the potentially corrupt code that has been potentially causing the server crashes might be here in the formation of party chat rooms? I hope this because
Cordovan said in another thread that G-Land has had all it's server hardware replaced and it still crashes, so they now suspect it's corrupted code somewhere. I don't want to send them on a wild goose chase as I want these problems solved as soon as possible as well (I love this game and want to be able to enjoy playing it whenever I can), but if these issues are linked? Then instead of an unknown amount of time (possibly years) trying to find that one piece of corrupted code, perhaps both issues (bugged party chat and server crashes) can be resolved simultaneously.
(yes, now I might be dreaming and stretching my hope far, but I can hope and dream can I not?)
EDIT: and I highly doubt it's an /ignore or /squelch issue (unless the game is changing peoples lists randomly), as this has happened with friends and we have been able to resolve it without changing our ignore lists (some of us never use that feature ever so our lists are empty).