Description of problem:
We are in the situation that some of our group names contain ( and ) signs, e.g.:

mygroup (mydepartment)

Since a recent update, a new feature has been added to pam_access described as follows in the sample configuration:

# The group file is searched only when a name does not match that of the
# logged-in user. Both the user's primary group is matched, as well as
# groups in which users are explicitly listed.
# To avoid problems with accounts, which have the same name as a group,
# you can use brackets around group names '(group)' to differentiate.
# In this case, you should also set the "nodefgroup" option.

which leads to the situation that groups with brackets are not recognised correctly, anymore.