Hello, your commit is great, thank you. If you need to change the initial PIN code for your privacyIDEA token, you only need to change one line of code in your privacyidea_radius.pm:
line 586: if ($pin_change_requested) {
to:
my $is_challenge = ($decoded->{result}{authentication} && $decoded->{result}{authentication} eq “CHALLENGE”);
if ($pin_change_requested && !$is_challenge) {
.. and it works now.