There used to be a setting in the Advanced options area called "Launch Browser Window in a separate process" which, if enabled, would force a new session with each new window. If disabled, all windows would share the same session. However, as of IE 5.01,
this is no longer an option.
If the computer has less than 32 megabytes (MBs) of RAM installed, this setting is disabled and all instances of Internet Explorer share the same process. If there is 32 MBs of RAM or more installed on the computer, the setting is enabled, which causes new instances of Internet Explorer to create new processes.
You cannot guarantee session state to be maintained over multiple windows. If you need to maintain data over multiple windows, use a key in the query that is tied to a cookie or a bean.
“Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning.” - Rich Cook