SAP Webdynpro Java UItable export to excel

Hi all,

I  have delopment a old method for export UItable to excel 2003 (.xls) , the method was development following:

Exporting Context Data into Excel Using the Web Dynpro Binary Cache

http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/edc2f3c2-0401-0010-8898-acd5b6a94353?QuickLink=index&…

I have two problem:

- The first is when I export big tables, the process is very slow and sometime the portal not work correctly, other time I can export my excel but is very very slow...

Also is very strange because when I export my UItable and select save the file have a size about 70 MB (also is very slow the process to save)  but when I go to the folder in show the properties file it have a sice about 1 or 2 MB.

- The another problem is if the user have another version of excel (more new) .xlsx, show a warning message,  we will upgrade these components:

SAP_JTECHF 7.01 SP9 (1000.7.01.9.0.20110512080700)  - now version

SAP_JTECHS 7.01 SP9 (1000.7.01.9.0.20110512080700)  - now version

But we are not sure if with the upgrade we can solve the problem with extensions .xlsx.

Please can you help me with this issue?

Thanks in advance

Regards

Mónica