a date like "06/25/08" results in June 25 1908.
this code:
dtstr = "06/25/08 07:00PM";
var d = new Date(dtstr);
platform.echo("date string = "+dtstr+" msec ="+d.getTime()+" d = "+d);
produces this:
06/25/08 07:00PM msec =-1941314400000 d = Thu Jun 25 19:00:00 PDT 1908