Upgrade from Sybase 10.0.4 to Sybase 11.5

Hi all,

 I am trying to upgrade my application from Sybase 10.0.4 to
Sybase 11.5. However, I find out that after I upgrade the Sybase. The
speed for openning the same query is much much slower than the speed
when I was using Sybase 10.0.4.

 Does anyone knows the reason and how can I solve the problem?
Is there some problem with the communication between Delphi 4 and
Sybase 11.5? (I am using Delphi 4.0 upgrade 2 and BDE 5.0).

 Thank you very much for your advice.