Originally raised here: https://answers.atlassian.com/questions/15201/using-sourcetree-on-a-local-apache-server-the-certificate-is-getting-rejected-despite-being-accepted-in-the-keychain

While SourceTree does supply the web.cacerts option if the user hasn't specified it, it appears some people are finding that the fingerprint needs to be supplied in the .hgrc too. SourceTree should make this easier to set up. MacHg prompts for this apparently.