1. A method for maintaining the security of a secured execution environment on a system comprising said secured execution environment and a second execution environment, the method comprising: maintaining a current state for said secured execution environment selected from among a group of possible states comprising: a standard input mode state and a nexus input mode state; and directing a flow of user input according to said current state at least through a secure kernel of both said second environment and said secured execution environment, including: accepting at the second execution environment the flow of user input; initially directing the accepted flow of user input from the second execution environment to the secured execution environment; determining at the secured execution environment whether said secured execution environment is in the standard input mode or the nexus input mode; and subsequently directing the initially directed flow of user input at the secured execution environment based on the determined input mode of the secured execution environment.