Informix DBError -41021 with PB 4.0.6

My application, created using PB 4.0 with the sixth release of patches, receives an error message from an Informix database residing on a Unix server being accessed through a Novell Network with TCP/IP: -41021 Connection Busy. You are currently making a database server request. You cannot make another request until the current request is finished. This error appears only to occur in a retrieve for a datawindow. When the error occurs, I issue a yield() and post another retrieve start event. This seems to solve the problem but the application is consistently GPF'n. I believe that this is the area that is causing the problem but I am baffled as to what approach I should use to remedy the problem. I am somewhat Informix illiterate and have little control over the customer's database and/or environment. The same application is running successfully on similiar systems using different databases such as Sybase, XDB, Watcom, etc., without causing a GPF. If anyone has encountered this problem, has any idea as to the cause of this problem, has a solution, or needs further information please contact me at: dstrasse@one.net Thanks for any help, Dean E. Strasser