Bicycle Mechanics - End of cable stuck in STI shifter

I was riding along today and my shifter cable snapped, right at the point where it mates with that little metal nub at the end of the cable that stays in the shifter. These are Ultegra 10-speed shifters. Now I can't get it out because the shifter will only let me downshift four gears, and I need to downshift all ten in order to pull the nub out. I can't pull on the cable because there isn't enough of it to pull on.

Any suggestions? Is it possible to disassemble these things? Thanks!

EDIT: Just found this thread. My problem is similar, except there is absolutely no actual cable sticking out. Just the little metal nub is stuck inside.

http://www.bikeforums.net/showthread.php?t=324132

-Engage the brake to view the shifter mechanism(loosen the brake so the lever moves all the way down to the bars)

-You see that shifter mechanism? Put a force on it, with something so when you downshift it will move (just as if you were pulling the cable out the other end and down shifting)

-You should be able to get the shift mechanism to its "set" position (10th gear)

-Youre going to need something small to poke the little nub out through the opposite end of the shifter (the one the cable feed OUT and into the shifthousing)

I suck at explaining, but it shouldn't be to hard. Have a shop get it out if you can't, you can really screw up the shifter if you bend/crack something

Once you have a clear view of the cable, try pushing it back to free it with a bent paperclip or similar. Try different gears until you can see the broken-end of the cable going to where the cable-head is located. I don't know exactly how the Ultegra likes to be cleared, but most are pretty similar.

Failing this - yes, drag it to your favorite LBS and ask to watch.

Everything markieta says is correct. But this only helps if the cable end hasn't dropped out of its "holder". My 105 shifter has broken two cables. First time the shop could eventually get it out. Second time they couldn't, so they called Shimano who sent a replacement via 2-day air (less than 1 year old.) Another shop's head mechanic told me you may have to work at it a long time, but he can always get the shifter to "10th gear" so the head is visible. I think mine broke and the head became dislodged inside. Poster above explains how to get where you can see, but if the head is indeed dislodged inside, I doubt any shop will disassemble it. They will either send it to Shiman or suggest a new one. If you're having trouble getting to shift more than a few times, chances are you may be stuck. That's what kept mine from being "field repairable."

I was able to grab just one wire of the cable with tweezers and carefully work it up when it happened to me. It was quite difficult.

There is a thread around here someplace where dtbaker61 (http://www.bikeforums.net/member.php?u=164664) details precisely how to drill a hole in the STI and extract the cable head that way. That is an excellent solution.