Are Proxy settings on a MAC profile specific

Quite a specific question. I have an luser who is getting a mis-configured proxy error which is served by the proxy server if the user dosn't have the proxy settings. Before I drive over there was wondering if anyone knows if mac proxy settings are specific to an individual user or global. E.g. if she's logged in as a different user to the one I setup last week will she have lost these settings?

I believe it's the most recent or 1 version back of OS X.

Thanks for any help.