I am trying to get a value to be returned to the calling program. I can not get the return value. I have done this before, but I do not know what I am doing wrong?

This is the calling program:
lnFind = space(10)
lnExec = SQLEXEC(lnConn,"Exec sp_seek_ssfno '128746586',?lnFind")


This is the stored procedure:
CREATE PROCEDURE sp_seek_ssfno

@lcSSfno CHAR(10),
@lnRet CHAR(10) output

AS



SELECT @lnRet = (select ssfno from tranhdr where RTRIM(LTRIM(ssfno)) = RTRIM(LTRIM(@lcSSfno)))

What am I not doing.