The problem:
Recently I have updated my system and also mecrurial. Today I tried to do some work with a repository hosted in another machine and I got the following warning:
warning: bitbucket.org certificate with fingerprint 81:2b:08:90:dc:d3:71:ee:e0:7c:b4:75:ce:9b:6c:48:94:56:a1:fe not verified (check hostfingerprints or web.cacerts config setting)
This really annoyed me and I did some search around what is necessary to do to get rid of this warning. And the solution follows.
The solution:
Add the following lines to the .hgrc file which is located in your home directory (if the file is not there create it).
[hostfingerprints]
www.bscmsrc.eu = e1:0e:46:81:37:20:33:aa:42:c0:98:d7:e9:7f:c6:19:7a:ee:d5:37
Assuming that e1:0e:46:81:37:20:33:aa:42:c0:98:d7:e9:7f:c6:19:7a:ee:d5:37 is the fingerprint for your host (displayed in the warning message).
And this should be enough to not see the warning message anymore.