LG GSA-T20N fails to overburn DVD+RW

Hi everybody!

I got about 4580 MB to write in a disc and I chose to use rewritable DVDs (Sony and Philips) to see if my Lg writer is able or not. Its firmware is WP03 and it seems up-to-date as well as its driver. My OS is Win XP SP3 and a few attempts have been made with Nero 6 (setting a number of blocks, as oversize option, corresponding to approx. 4690 MB) and with Imgburn which, as other people report in case of dvd overburning fail, manages to burn only 2295104 sectors (instead of continuing until the end, in my case 2344496). Both programs have obviously overburning option activated. I’m afraid my LG writer doesn’t support DVD overburning.
What does this depend?

Should I use a non rewritable DVD?
Should I use a more recent version of Nero? Or perhaps would I need some changes at firmware level or at key registry level?
Does anyone know if my LG writer supports DVD overburning (since I know that it does support CD overburning)?