Errors on forum topic node imports

I don't see where anyone else is having this issue but I'm getting the following error on each forum topic node for which an import is attempted when running migrate:

MigrateException: reset() expects parameter 1 to be array, null given File /home/ranchom/drushd7/modules/forum/forum.module, line 331 in MigrationBase->errorHandler() (line 707 of /home/ranchom/drushd7/sites/all/modules/migrate/includes/base.inc).

Can someone look into this ??