unable to run keytool

I managed to create a keystore file using keytool but when i select it from the publishing settings in unity i get the error message “unable to run keytool; do you have the jdk installed?”. I have the jdk installed. Anyone knows why unity can’t find keytool?

http://forum.unity3d.com/threads/62137-Android-Signing

go to this link

I can’t to make unity account anyhow!!!