From Tapestries MUCK
This function will return a list that contains the full names of all the sub-properties contained by the given propdir.
If not given, object defaults to the trigger object. If a pattern is given, the sub-properties in the propdir are each compared against the smatch wildcard pattern, and only those that match are returned in the list. This comparison is only done on the last part of the property name after the last /.