The link provided by Jeff indeed works though it assumes you have a you have a default group where users are added to. I simply replaced:
group=Group.objects.get(pk=1)
by
group,created=Group.objects.get_or_create(name="everyone")
If you want tighter integration & more features there is also django-auth-ldap which gives you you more control over how ldap users/group are mapped onto django users/groups.
For debugging the ldap connection I found this blog post useful, in particular the command for testing the ldap connection with ldap-utils:
ldapsearch -H ldaps://ldap-x.companygroup.local:636 -D "CN=Something LDAP,OU=Random Group,DC=companygroup,DC=local" -w "p4ssw0rd" -v -d 1
If you are using ssl there is also the issue of getting hold of a certificate will play nice with. Either you extract it from the server, or you can follow these instructions to generate your own.