I received another one letter from ALGENCAN developers. They informed me about some changes they made according to my suggestions (like using numpy.array instead of Python list etc).
So I don't think all is implemented very nice for now, especially the way they handle linear constraints in input data. But anyway it's already much more better and could be connected, have I enough time - now I'm a little bit out of GSoC schedule, so, maybe, I will write ALGENCAN binding in September or so. It still requires much more work than lbfgsb or tnc or cobyla (from scipy), because it has much more input parameters and non-standard (vs scipy) interface. Maybe I will write bindings to the ones before GSoC finish.
Also, ALGENCAN can use 2nd derivatives (as well as HESSmult func), but 2-nd order problems (all those d2f, d2c, d2h) are not implemented in openopt yet.
So, I sent them some more suggestions, like using iterfcn for to enable real-time openopt graphical output and user-defined stop criteria.