I can't install the ADT plugin for eclipse 3.5.2 on windows XP(32bit)

I had installed jdk,sdk,eclipse,and set the path.i will show the jdk-version,sdk.

jdk version test:

C:>java -version java version "1.6.0_10" Java(TM) SE Runtime Environment (build 1.6.0_10-b33) Java HotSpot(TM) Client VM (build 11.0-b15, mixed mode, sharing)

sdk test:

C:>android -help Usage: java [-options] class [args...] (to execute a class) or java [-options] -jar jarfile [args...] (to execute a jar file)

where options include: -clie开发者_高级运维nt to select the "client" VM -server to select the "server" VM -hotspot is a synonym for the "client" VM [deprecated] The default VM is client.

-cp <class search path of directories and zip/jar files>
-classpath <class search path of directories and zip/jar files>

the eclipse version: Eclipse IDE for Java Developers---Eclipse Galileo SR2 Packages (v 3.5.2)

but have a question when i install the ADT: i install it online,the url the question is :

you are installing software that contains unsigned content.The authenticity or validity of this software cannot be established.

Just accept it and allow it to install.