this is what my car was doing everytime i went round a left bend the handbrake light came on, i thought nothing of it but it ended up being a warning about my slave cylinder which i have had to have re-placed, so i would check that just in case
This happened to me and I finished up driving my Brava for quite a while with the handbrake light flashing then eventually staying on. It turned out to be the slave cylinder.
I had to have it replaced - but saying that, at least it turned out to be cheaper than a whole new gearbox.