A rare case of symbol ?misbehavior? has been discovered, if all of the following parameters are met:
After creating a new symbol, containing only ONE object with an assigned class name and using the class settings in the attributes palettes, and if this symbol has never modified in any way, i.e adding a second object or converting a rectangle to a polygon etc., then when converting this Symbol to Group, the object will take on the attributes of the default class, which in most cases is the none class. This is due to the symbol actually converting to an object, rather then to a group.
The fix for this problem is, to simply add an object to the symbol, save it, and then re-enter the symbol and deleting the bogus object. Now, when converting Symbol to Group, it will remain a group and will retain the original class attributes.