Need Help about Professional Subtitling

[kei_siuip]

Hi, I am setting up an post production studio.
I'll like to provide subtitling service to clients.
I want to know are there any subtitling software which support VITC Timecode?
For example, if I have a video file (mpeg4, mpeg2, MOV, avi, etc) with Timecode display on screen (PAL/NTSC/DF/non-DF , etc),
can I use a subtitling software with a PC to make subtitle (with the same timecode of the video file)???
So that my clients can use the subtitle file to sync with the original Beta/DigiBeta/HD tape?
Also, the subtitle file should be converted to support profesional DVD authoring Tools.

Are there any subtitling software which have these functions?

Plz Help

[kei_siuip]

Any help??