This is an extension of request #13989
It looks like in some environments the port used by the client is set to an empty string (proxies, some network appliance?) and and the Gitolite shell is not happy about it.
This can be seen in /var/log/tuleap/git_http_error_log:
WARNING: Use of uninitialized value in concatenation (.) or string at /usr/share/gitolite3/gitolite-shell line 239, <DATA> line 1.