Just thought I would follow this up:
Yipee I have fixed it. It is working great now. . . . . for the moment.
I tried lots of things, rooting the phone so I could modify the gps config file, followed all the suggestions about recalibrating it, installed FasterFix. Nothing. In fact it got so bad that it just wouldnt work at all. My next step was going to be to install a different rom to see if that made it better. I had one already to go, but first it says to perform a full factory reset. so I did this. mmmm I thought, I wonder if that makes the gps work... and sure enough this is what seemed to fix it. It now locks on with in 10 secs and is perfect, just as it was when new. I didn't bother with the rom just carried on with the original one after the reset.
So I can recommend you do the same - perform a full factory reset.
Remember you will loose everything you have installed and all your contacts so make sure you back these up first. I then went through reinstalling all my apps and GPS is still working well. Something must have go in there to stop it working but I havent found what it was yet. Fingers crossed it keeps on working.
HTH.
Keith.
