This exception is thrown on:
The code is here
private void setComponentProperty(PropertyDescriptor propertyDescriptor, Object value)
Method writeMethod = propertyDescriptor.getWriteMethod();
if (writeMethod == null)
throw new IllegalArgumentException("Component property " + propertyDescriptor.getName() + " is not writable");
The problem was on the tag class, because it does not convert sortable to the proper value. With myfaces-builder-plugin, this tag class is now generated, so this problem was solved on
TOMAHAWK-1259. I have tested and now this is not thrown.