Flash thinks my variable is a command

So I’m setting up some variables for a Flash that will be sending the data to an e-bay type payment program.

        my_lv.taxRate = "7.1";
        my_lv.return = "http://www.mysite.com/return.html";

Tax rate is just in there to show an example. Flash is having problems with my “my_lv.return” variable. It for some reason thinks it is a command. (I guess ‘return’ must be some type of AS command)
But I can’t change the name of the variable or my shopping cart won’t understand it! So what to do?