>Now I know the parameter is being sent, because if I change this code to do a TYPE check on the parameter, it works. Apparently, PARAMETERS() is always returning < 1....

Is it because there is no paramter statement? Try either adding the parameter statement, or try using PCount(). You should alswyas use PCount() anyways, because it uses the parameter count for the current program, instead of Parameters() which counst the parameters for the last program called.