There is another JavaScript bug in Oracle WebCenter Interaction 10gR3 (\bea\alui\ptimages\imageserver\plumtree\common\private\jsutil\LATEST\ptutil.js). My current version of this file 'ptutils.js' is 334989. You can find the bug in line 116:

                if (srcObj.Class && (srcObj.Class == 'Array') && (typeof srcObj[i] == 'function')) { continue; }

which should be

                if (srcObj.Class && (srcObj.Class == 'Array') && (typeof srcObj[i] == 'function')) { continue; }
                if (typeof srcObj[i] == 'function') { continue; } // <-- This line is missing