why cell-phone does not support 3gp-subtile and mp4-subtitle?

[fulcrum]

I generated one mp4 file and one 3gp file with subtitle by MP4BOX.
I put two files in my cell phone(nokia N95), but the subtitle could not shown on the screen.
I download them into my Iphone device, only the mp4 file`s subtitle could be displayed.
The Realplayer version No.in Nokia Portable device is s60.30.45.01.

I tested 3gp file with Realplayer on PC (version 10.6 ,it is released on June 2007), the subtitle still couldn`t be shown. The error message was: this format is not available:
： video/x-rn-3gpp-text

Why cell-phone version can't support subtitl, could you please tell me the reason. Thank you very much.

[Ghitulescu]

Ask Nokia - they are obliged to support the phone at least in the warranty period (I hope you bought the phone through the official channels).

[fulcrum]

Ask Nokia - they are obliged to support the phone at least in the warranty period (I hope you bought the phone through the official channels).

I tested it not only on Nokia, i also tested many other brands of cell-phones, but i got the same result. why? The difference is the subtitle-3gp can't play in PC-version but it can play without subtitle in cellphone-version, does this mean the cellphone-version can "recognize" the subtitle?

If the subtitle-3gp can't play on cell-phone, where it can be played?

[Ghitulescu]

Cellphones have a different CPU and operating systems as PCs do. Parallels between the various versions of the same software are irrelevant.

If other movies w/ subtitles are working ok on your Nokia, then is a problem of mp4box.