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 - both of which
are not receiving enhancments. (Excluding security issues)
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.