Apple has just released the new version of it’s MacOS operating systems called Mountain Lion and of course the VMware View Client for Mac 1.5 is already compatible with it. A new function in Mountain Lion verifies the identity of a software developer and checks if a packet is signed. This is called Gatekeeper. You can directly download the 1.5 client from this page: https://my.vmware.com/web/vmware/info/slug/desktop_end_user_computing/vmware_view_clients/1_0.
Image source: http://blogs.vmware.com/.a/6a00d8341c328153ef016768be9dda970b-650wi