Hi Liz,
I don't think your -g value is valid. That option is used to specify the type of spatial index and, if applicable, spatial index parameters. I believe your possible options are
GRID,<a grid size>
AUTOMATIC
NONE
RTREE
Which ones you can use depends on the DBMS you are using and the geometry storage type used to create the feature class. (In your example, the -k was not specified, so whatever the GEOMETRY_STORAGE value you have set in your DEFAULTS keyword in the DBTUNE table is what will be used to create the feature class.)
However, that error message seems to indicate there's something about the information passed that the DBMS didn't like. Did your DBMS error log file show anything?
-Kim