Problem calling Informix stored procedures from SQL-Windows

One of our SQL-Windows (5.01) developers has spent many hours trying to figure out why SQL-Windows is apparently not passing parameter values to a Informix (7.11) stored procedure. The stored procedure is supposed to return values back to SQL-Windows for populating a table window. The procedure uses parameters passed in to determine what rows should be returned, pretty standard stuff. We have narrowed it down to this: when we modify the procedure such that it does not need any parameters passed to it in order to return rows (just for debugging purposes, of course), SQL-Windows successfully fetches the rows which come back and the table window gets populated. However, when the procedure is modified to require even just one parameter and the SQL-Windows code is altered to pass the procedure one parameter value (an INTEGER), we get a stored procedure SQL error which says that the parameter variable is undefined (i.e. it did not get passed to the procedure). We have tried passing in the parameter with a bind variable AND with a literal value, but still no luck. The developer working on this has even talked with at least one developer at GUPTA who was involved in the implementation of this SQL-Windows feature and of course they had no trouble doing what we are trying to do. It remains one of the great mysteries in our software shop and we are very desperate for some success with this. Does anyone have any experience, suggestions, insight or just "something to try or think about" on this? Anything would be much appreciated. Thanks, John Hess Aeronomics Incorporated John_Hess@Aeronomics.com