fetch(3): Authentication error when URL https://

Hello.

Creating a port, I need to fectch sources from a site whos URL is
https://xxx.xxx.xxx.

Doing so, I end up with an "Authentication error". This makes the fetch
process in the port's Makefile impossible.

I tried to fetch the source tar-ball via "wget(1)", but this also fails,
wget suggests to use option --no-check-certificate:

Connecting to launchpad.net (launchpad.net)|91.189.89.223|:443... connected.
ERROR: cannot verify launchpad.net's certificate, issued by
`/C=US/ST=Arizona/L=Scottsdale/O=GoDaddy.com,
Inc./OU=http://certificates.godaddy.com/repository/CN=Go Daddy Secure
Certification Authority/serialNumber=07969287':
  Self-signed certificate encountered.
To connect to launchpad.net insecurely, use `--no-check-certificate'.


Doing so succeeds. Is there a possibility to enable this
--no-check-certificate" with fetch, too?

Regards,
Oliver