It is possible to know if users are logged in and logged out on ms crm 4.0?

i want 开发者_JAVA技巧to do little chat on ms crm 4.0 and i want to know if i can to catch all users that currently loggedin into ms crm 4.0?

Not natively. You could do a number of things to maintain a list of users who have recently made requests to CRM, but that's not quite the same.