IronPython is certainly not supported by scikit-learn, and I doubt that it'll work without significant effort. The NumPy and SciPy for IronPython document describes the porting effort required for SciPy, and this has certainly not been done for scikit-learn, which too depends heavily on Cython-generated C code (unless someone did the porting effort but didn't advertise it on the scikit-learn mailing list).
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…