[jetty-users] problem with Running Jetty-6.1.x

[jetty-users] problem with Running Jetty-6.1.x

From: Fatemeh Nakhaie <fatemeh.nakhaie@xxxxxxxxx>
Date: Mon, 27 Jul 2009 08:53:44 -0700 (PDT)
Delivered-to: jetty-users@eclipse.org
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Hi . I download jetty-6.1.12 from codehaus
In CMD, I typed jetty installion directory and then typed:

java -jar start.jar etc/jetty.xml
but this messege is shown :

Unable to access jarfile start.jar

why? what should I do?
regards...