4.44, but 5.24 is available in parts of the world but not here yet.

from expansys forums:

So, today i've got 5.24 firmware installed. I have used older firmware
only for several days, but even now I can see some very good changes:

1. You can see Caller ID with any wallpaper - when someone calls you,
the wallpaper becomes much much lighter, but it stays there. I think
this soluton by Nokia is better than changing color of fonts, as some
of members requested. It is really cool. It is really better and
smartder than in older 40series nokias.
2. Icon Services is now called "Web"
3. new 'Instant messages' in the 'messages' menu
4. After you take a picture, main NAVI button says 'Send' but not
'Delete'
5. Music player playlist automaticaly sees all the mp3 from mmc, no
matter in which folder where they are.
6. When the phone asks you to choose the folder (e.g. when you define
where your photos will be stored from camera options menu), main NAVi
button is 'SET' instead of 'Open', if you want to open folder (go
deeper) have to choose Options->Open folder

Sorry, I'm using 6230 only for 2 days. After 1st day I managed to
squeze it accidently - the phone has lost it's internal memory (Free -
0kb, used - 0kb, i changed the main microprocessor at the service
center and when I got it, it had 5.24 firmware on it. (25-11-04)

waiting for the normal changelog :)

P.S. Lithuania

Chris P Bacon