evenif u will acheive this you will have problem, coz browser will also do some function in this case, like Mozilla will start new tab.
so try some thing else.
Why you want to do this, probably we can suggest some thing different.
it has solve your problem,
when you will press ctrl+t(or any other combination) it will return you perticular keyCode using which you can identify the key combination.
in IE you can capture keyCode using window.event.keyCode
use document.onkeypress to capture keypress event on whole document. see this also.
hope this will solve your problem.
following example may help you:
this example will work in IE 6