SAP Netweaver Portal pages are displayed with junk characters

SAP Java portal NWA , portal, iview manual testing pages  are giving junck page.  The portal is unusable state. We are on SAP EHP1 FOR SAP NETWEAVER 7.0.2.

Tried with the different browsers IE , google chrome but no change in the behavior. The initial resolution or work around suggested by SAP was to restore the portal with the last known good condition of the portal backup.

We restored the system with the good database backup but after couple of days or in a week, the issue resurfaced again.

The root cause found after looking at the logs and with SAP help, we narrowed down the issue as below:

The content compression is made twice: Once by the webdynpro runtime and again by HTTP provider. 

We desabled the webdynpro compression by setting the parameter ZipResponse to the default value ' false ' 

http://help.sap.com/saphelp_nw70/helpdata/en/43/8a1a8ece230c8ce10000000a11466f/content.htm