The log seems to only contain one error but instead there are several hundred rows with that same error. Here it is:
BEGIN failed--compilation aborted at /usr/local/ispconfig/server/scripts/vlogger line 148.
piped log program ' /usr/local/ispconfig/server/scripts/vlogger -s access.log -t "%Y%m%d-access.log" -d "/etc/vlogger-dbi.conf" /var/log/ispconfig/httpd' failed unexpectedly
Can't locate Date/Format.pm in @INC (@INC contains: /etc/perl /usr/local/lib/perl/5.10.1 /usr/local/share/perl/5.10.1 /usr/lib/perl5 /usr/share/perl5 /usr/lib/perl/5.10 /usr/share/perl/5.10 /usr/local/lib/site_perl) at /usr/local/ispcon$