It's a stand way that if you want to tell the Java to use the proxy by using the System property. It may cause some side effect if you don't want to maven to share the proxy with Fuse ESB. But for most users the proxy setting is kind of system wide setting, and maven setting supports to set the nonProxyHost that you may consider to use.
Edited by: njiang on Apr 22, 2011 11:06 AM
There are some flaws in you statement
System wide settings should be set on System level, not in some "random" program
The calling application might propagate the settings to the application it calls, but not visa versa.
If an application decides to use the config of a different application it should be consistent and clearly documented. This behavior happens only when using maven bundles, which is standard but not required.