ok
I have solved the problem.
in the default server.xml file tag like this,
<Host name="localhost" appBase="webapps"
unpackWARs="true" autoDeploy="true">
<!-- SingleSignOn valve, share authentication between web applications
Documentation at: /docs/config/valve.html -->
<!--
<Valve className="org.apache.catalina.authenticator.SingleSignOn" />
-->
<!-- Access log processes all example.
Documentation at: /docs/config/valve.html
Note: The pattern used is equivalent to using pattern="common" -->
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
prefix="localhost_access_log." suffix=".txt"
pattern="%h %l %u %t "%r" %s %b" />
</Host>
but I have removed that and changed like these
<Host appBase="webapps" name="example.com" unPackWars="true" autoDeploy="true">
<Context path="" docBase="myproject" debug="0" reloadable="true"/>
</Host>
<Host appBase="webapps" name="www.example.com" unPackWars="true" autoDeploy="true">
<Context path="" docBase="myproject" debug="0" reloadable="true"/>
</Host>
and than I have changed
<Connector port="8080" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="8443" />
like this
<Connector port="80" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="8443" />
now it works:)