It depends on the version of the
Servlet API you need.
- Tomcat 3 supports the 2.2 API
- Tomcat 4 supports the 2.3 API
- Tomcat 5 supports the 2.4 API
As of December 3, 2003 Tomcat 5 has been declared stable.
There are 2 flavors of Tomcat 4: 4.0.X and 4.1.X. The 4.1.x version is
still slowly receiving new enhancements but this
trend is subsiding while more attention is paid to Tomcat5.
Version 4.0.X is only receiving security fixes. Both (4.0 and 4.1)
are suitable for production.
Version 4.1.X is significantly faster than 4.0.X.
Tomcat 3 I know nothing about with respect to performance and
maintenance. AFAIK - it
is still receiving security fixes. The
Tomcat home page should have the correct recommendation.