Weblogic Timeout Attributes

Hi,
We are using Weblogic 7.0 , recently we keep recieving "weblogic.transaction.internal.TimedOutException: Transaction timed out after 31 seconds" error in the application.

Following are the values set for the timeout attributes in the server:
Post Timeout Secs - 30
Duration - 30
Https Duration - 60

All these attributes are left with default value. Can tuning up these value have effect on the above exception? I believe these are development environment values. As am getting this error in production env, i believe there must be a suggested optimal value for these attribute. Our application is used by more than 50 concurrent users and some of the db queries may take more than 30 secs to return results.

If any of you have configured above attributes and have seen any visible in the performance of the application or if you have any suggestion to get rid of this timeout error Please share your experience.

Thanks
Vishy