Gurk: Check out what WS said. The principle is simple, just stripe code on track 4, and the interface will spit into the sequencer to synch up.
In practice, things get a little bit more fun - I think most sequencers nowdays use MTC (MIDI Time Code), which will allow you to drop into the middle of a song and have everything lock up. Other formats you'll see is FSK (Frequenct Shift Keying), which is outdated at this point. The only thing you can do with FSK is start each take from the beginning of the song - it won't drop in like MTC will. Older equipment, such as the Roland TR-707 drumbo, used this. The industry standard for pro's, though, is SMPTE. I use SMPTE and like it a lot, but there are different variations of it, which becomes a nightmare when you A) forget what one you used six months ago, or B) start swapping tapes. Document everything, find a method that works, and stick with it!
Another thing you'll want to look at is defeating the Dolby or DBX on the stripe track - because of the de-emphasis used by these noise reduction systems, the code waveform becomes corrupted (the square waves of the modulated code round off) and the clocking of the sequencer might not be able to read it, unless you really boost the recording level... and by then you have crosstalk into the other audio tracks, so you hear this nassssty whining sound in the background. I had a Tascam 244 back in my 4-track days; modifying the machine to defeat dbx on track 4 was as simple as breaking a trace on the PCB between the dbx chip and the recording preamp IC. I hope most newer machines take this into account, and have a switch on them instead.
One last thing - it really helps to have all your equipment share a common ground. Even with my 238 (eight-track on cassette), I was getting some crosstalk from the striped track - it's almost as if SMPTE has some RF component that was bleeding in. Bringing the computer, rack, and synths to a central ground fixed the problem.
Hope this helps!