  All the possible super-conducting order parameters for the LaOFeAs system are
classified by their transformation under the complete crystal symmetry. The
general forms of the super-conducting gap functions for each class are
discussed. We find that the gap functions in such a multi-band system belong to
three types, full gap, nodal type and finite {}``Fermi arc'' type. Possible
physical consequences caused by different types of gap functions are also
discussed.
