[ODE] Joint solving differences in Quickstep vs StepFast1

[Mohsin Hasan]

I created a few prototypes of ragdolls and cloth simulation both using hinge
joints. Both of the demos work fine with StepFast1 but if I try these demos
with Quickstep the ragdolls start jittering (as if the joints are randomly
being applied an impulse) and continue that way even after falling. The
cloth on the other hand just explodes after a while. If I set ERP to a very
low value (say 0.01) the jittering sort of gets very low and occasional but
the results are not that good (mostly Ragdoll joints start breaking etc.). 

Both of these samples work great with StepFast even with an ERP as high as
1.0. Any ideas what could be the issue of joint solving by QuickStep Vs
StepFast? Anyone else also having same issues? I am willing to share the
source code if anyone wishes.

Regards,
Mohsin