Another bug from the tracker, reported by Mike Stramba. A duplicated Py_XDECREF in the wrong place made assigning arrays from Vector objects not work. Also, fixed nasty bug in C API of idproperties (the function to look up a property from a group was broken). Fixed a memory leak too. In addition, made "del group['property']" delete properties from group; previously this would just crash (or at least it should have). Added a small addition to the example in the epydocs for IDGroup.