Session timeout problem in ASP.NEt application when accessed remotely

Question

I have a ASP.NET application, when I access this application from the local computer it runs fine. But When I try to access this application remotely i.e someother machine then there is a session time out problem every now and then. This doesnt happens with all cases. But many times it happens. If any body came across this type of issue let me know. thanks Ninad