[squid-users] problem with custom pages and acl

These are my acl's:-

acl advertimages url_regex "/usr/local/etc/squid/adverts.txt"
acl deniedsites url_regex "/usr/local/etc/squid/squid-deny.txt"
acl allowedsites url_regex "/usr/local/etc/squid/squid-allow.txt"
acl porn url_regex "/usr/local/etc/squid/porn.block.txt"
acl noporn url_regex "/usr/local/etc/squid/porn.unblock.txt"
acl antiworms url_regex "/usr/local/etc/squid/wormblocking.txt"
acl downloads urlpath_regex "/usr/local/etc/squid/download-deny.txt"

acl okTime time MTWHF 09:00-18:30
acl downloaders proxy_auth "/usr/local/etc/squid/download-users"
acl students proxy_auth "/usr/local/etc/squid/student.users"
acl staff proxy_auth "/usr/local/etc/squid/staff.users"
acl volunteers proxy_auth "/usr/local/etc/squid/volunteer.users"
acl password proxy_auth 300
#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
http_access allow allowedsites
http_access deny deniedsites
http_access deny advertimages
http_access deny antiworms
http_access allow noporn
http_access deny porn
http_access allow downloaders
http_access deny downloads
http_access deny !students !staff !volunteers
http_access deny students !okTime

deny_info ERR_DOWNLOAD_ACCESS_DENIED downloads
deny_info ERR_PORN_ACCESS_DENIED porn
deny_info ERR_HHDENY_ACCESS_DENIED deniedsites
deny_info ERR_ADVERT_ACCESS_DENIED advertimages
deny_info ERR_STUDENT_ACCESS_DENIED students !okTime

When the acl rule "http_access deny students !okTime" is happening the
custom error page ERR_STUDENT_ACCESS_DENIED doesn't appear, just the
normal ERR_ACCESS_DENIED page appears.

All others work/display ok. Is this becuase it is an acl that is made up
of 2 acl?

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