> I have a calculated field in one of my TIB_Query and put needed statement

in the OnCalculateField event:

I believe the 4.2 Fn sub-release should have this issue resolved. Please
test it and let me know.

> with AField do

You may want to check for AField being Assigned() or not. If it comes in
unassigned that means you are responsible to set the values of all the
calculated fields yourself in one shot. That is what the CalculateAllFields
property is for.

Thanks,
Jason Wharton
CPS - Mesa AZ
http://www.ibobjects.com