Problem with cachedupdates in Delphi 4

I have two Querys Master-Detail:
 QueryMaster: Without cachedupdates.
 QueryDetail: With cachedupdates and datasource DQueryMaster
Before do a post in QueryMaster updatespending in QueryDetail is true,
after I do a post in the QueryMaster the updatespending
in QueryDetail is false, I have lost all my data in QueryDetail.
I need to do this in this order:
 1) Post in QueryMaster
 2) Applyupdates in QueryDetail (but i can't do because
don't exists cachedupdates)
When I work with Delphi 3 this works well.
What is the problem? Is a bug in Delphi 4? Am i doing something wrong?
I am using Delphi 4 Client/Server with all patches and Informix online.

Please help
  Miguel Angel Ferrer