Java APIs

Hi,

I've an error while compliling my java files.

The error is shown below:

MyServlet.java:1: package javax.servlet does not exist
import javax.servlet.*;
^
MyServlet.java:2: package javax.servlet.http does not exist
import javax.servlet.http.*;
^
MyServlet.java:6: cannot resolve symbol
symbol : class HttpServlet
location: class MyServlet


My environment is Windows 2000 Professional
I have Java installed on E:\server\java\j2sdk1.4.2
Also Tomcat installed on E:\server\tomcat

I have set my Envirenment from My Computer > Properties > Advanced > Environment Variables
Here is my environment variables

VARIABLE NAME VARIABLE VALUE
------------- --------------
ANT_HOME E:\server\tomcat
CATALINA_BASE E:\server\tomcat
CATALINA_HOME E:\server\tomcat
CATALINA_TMPDIR E:\server\tomcat\temp
CLASSPATH E:\server\java\j2sdk1.4.2\lib\tools.jar;
JAVA_HOME E:\server\java\j2sdk1.4.2
TOMCAT_HOME E:\server\tomcat
path %SystemRoot%\system32;%SystemRoot%;%SystemRoot%\system32\WBEM;C:\winnt\system32;E:\server\java\j2sdk1.4.2\bin


What should I do to get success on compiling my java files ??
How to ensure that the package required on compiling is exist ??

Thanks in advance.