Dear R-Users, I'm searching for somebody who can support me or even likes to collaborate with me in setting up an R-package for "constrained maximim log-likelihood" parameter estimation. For example fitting the parameters of a MA(1)-APARCH(1,1) model for a time series of 17'000 points (e.g. the famous Ding-Granger-Engle mode) takes about 10 minutes with the existing optimization algorithms available under R. Modern state of the art algorithms, like SQP algorithms as implemented in Gauss, Matlab, Ox, take about a few seconds. I tested this finding with a free constrained SQP solver written in FORTRAN under R and found these results confirmed. I got the results in a few seconds instead of a few minutes! Now I'm looking for a collegue who has the experience in implementing FORTRAN Optimization Code in R, calling the objective function and optionally gradient and hessian from R functions. I have already inspected a lot of Fortran, C, and R sources from the base package, but I didn't succeed so far with a reasonable effort. Many thanks in advance Diethelm Wuertz