which application server to use...?????

hello,
iam developing an email-system(using servlets), for that to succeed in stress testing(from thousands of users
who hit our site simultaneouly) which application
server is to be used. Also can u provide the Connection Pooling program in java for that application server u suggest.
Aslo please explain me breifly why and what features
are there for ur suggeting server..?
thanx..

I'm not convinced that posting the same request in several different forums will solve your problem(s) any quicker
Without going into your task any deeper, first issue would how much are you prepared to pay?
If you have deep pockects then the world is yours and there are any number of web servers available
otherwise take the apache/tomcat road as they are free!
Also have you checked poolman?
http://sourceforge.net/projects/poolman/
for your connection pooling issue