There is a proxy settings dialoge available in Jenkins, but the user has to manually specify the proxy settings for her environment. Also in Jenkins there is no support at all for processing proxy.pac files.

The use of the proxy-vole library at least to fill in the defaults would make the use of Jenkins in a network that requires the use of a HTTP proxy to access the Internet a lot more comfortable and intuitive.

From the description page at:

https://code.google.com/p/proxy-vole/

"[proxy-vole is a] Java library to auto detect the platform network proxy settings. The library provides some proxy setting search strategies to read the proxy settings from the system config (Windows, KDE, Gnome, OSX), browser config (Firefox, IE), or environment variables, ... and provides you an ready to use proxy selector. "