javascript window.open not working for SSRS 2008 Report Hyperlink

Hi,

Requirement: Open SSRS report hyperlink in a new window/tab. 

I am using Windows Server 2008 R2 SP1 and SSRS 2008 R2 SP1. Internet explore 8.0 and  9.0. The following link is not working in SSRS report "Go To URL" TextBox Property code:

="javascript:void(window.open('http://www.google.com', '_blank')"

On click of hyperlink, nothing happens, no reaction.

While, the following link is working (opens link in the same window):

="http://www.google.com"

This issue is reproduced in production server and needs to be resolved immediately. Can anyone help me out to resolve this issue quickly.

Thanks,

IT People