More experiments with the TV out and the 3.5mm connector...
Well, the 3.5mm connector is very sensitive and won't accept anything that has non-standard size (certain headphones has slightly thicker diameter). Basically it'll detect good quality cables, but won't give a damn to chapalang cables. Also, how fast/slow you insert/unplug the jack will also affect the detection.
I tried a cheap china made AV cable for iPod video, totally cannot display (weird image) and produce annoying noise. Then I also tried it on the iPod video, it won't even detect it (it was OK and absolutely functional when my gf first got it, I guess the iPod 3.5mm port is also very sensitive). I use the original Nokia AV cable, and it was functional. So don't waste money on chapalang brand cables cause it's not worth it and waste money if so happened you lost your cable or cable spoiled (touch wood touch wood)...Also I found that if I unplug the AV cable too fast the phone will not resume to normal handset status and will remain on TV out...
On the other hand, the headphone cables. Yeah, I bought a Griffin (I think it's spelled that way) headphones RM100 (dang!), the diameter of the jack is slightly thicker so when insert it into the connector it'll just detect it as TV out no matter how hard I try. Then no choice I bought another good quality Sony headphone (RM119), an in-ear earbud headphones like those bundled with SE W series phones except it came with 50m cord + 1M extension cord (also the detachable ear frame that'll secure the headphone during jogging etc). No just the quality is even better, the rubber also very soft and easy on the ears, and most importantly the sound character goes really well with N95 8GB. Also, it has an L-shape connector. Highly recommend this, for the price I think it's really a good one.

I probably will give the Griffin headphones for my brother. However, the Griffin actually very nice also (just not as clear as the Sony headphone), and it doesn't need as much power to drive the volume as the Sony headphone (means the Sony headphone will be softer compared to the Griffin with the same volume setting). I would have stick to that one if the connector has "normal" size...