i know this has been discussed before but im not clear about this so:

is there a HARDWARE or SOFTWARE issue
that we cant use the remote controll headsets we have from our old N95 lets say ?

As I said before - could we have a sticky for this? I've not been a member long and I want the same answers as the OP but it seems to come up in a separate thread at least twice a week...?

Then maybe also someone at Nokia will take note of it (OK, very long shot) or some enterprising DIYer with time on their hands might find a solution.

I'm not sure if your question is only about the old N95 headset or remote controlling ones in general. However, I have a bluetooth stereo HS from Plantronics and it's been working fine so far, at least regarding RC functionality. "Next track" function used to not work with Mediabox, but it does with the newest version.
Also, I believe there's a thread somewhere here teaching how to use the HS included with the N900 to manipulate the Media Player...

I think most of us know by now that AVCTP over BT works fine. It's just that some of us want wired headsets for one reason or another, and not the one shipped with the N900, but one with a jack and transport controls.

I think it was discussed before, and there's no chance wired remote control would work due to lack of hardware support.
But what you might try to do is connecting a bluetooth AVRCP device AND your headphones directly to N900 at the same time. I was using cheap BT-214 clone to switch songs while listening to music over FM transmitter. It was a bit tricky to set up, but worked flawlessly. So I guess you'd be able to listen to music over your headphones while connected to bluetooth (at least with some minor hacks or tweaks). Didn't try that, since just bought a good pair of BT headphones and forgot about wires.
BT-214 make a good remote control actually.

BTW another option is try to get one of those cords that have male jack on one end, and mic, answer button and female jack on the other end. They all have different wiring, so might be hard to actually find one suitable for N900, but if you do - you'll be able to use it in the same way as a bundled one at least, while still listening to music with headphones of your choice.

The headphone jack is not active when BT is paired. Perhaps someone can write a workaround for it - but I for one suspect that I'll be long gone from the Maemo/Meego world by the time that happens, if ever.

I think that if you're fine with the sound quality over BT (the 214 for example is actually pretty respectable, considering) then there is no problem - and given the low-grade audio most people are used to, I guess many will find the BT audio perfectly OK.

The problem is when you throw in highly isolating, four-figure, custom-moulded in-ear monitors into the mix: Running that over BT (and I'm doing so when I don't have the iPhone or one of my PMP's with me) is... well, slumming it in the extreme.

@bennypr0fane

i also have a pair of bluetooth NOKIA headset but i think i am having enough battery problems without ANY bluetooth use so...not really an option for me (i used them with the n95 also and let me tell you, they suck the life out of phones)

@little_beat

"I think it was discussed before, and there's no chance wired remote control would work due to lack of hardware support."
please expand on what kind of hardware support exactly?
i mean the tv-out cable works so its probably the same jack port as in n95 (or maybe i dont know what im talking about...) so it would be a software problem to take the signals from the headset to the media player

*but i dont really know how the wired remote control works maybe someone could tell me about that...