Not work without internet connection

[Tab10id]

We use intranet and internal mail server. Mailnag everytime check internet connection that we will never have. For now I changed connectivity_test to ping and set www.google.com/de to 127.0.0.1 in hosts but this is a horrible hack. I think that right idea is to make it possible to disable connection checking but I will be fine if you decide just to make hostname for check configurable. Thanks.