web issues: blocking email, chat, and porn

[Dan Lester]

This is a mixture of various common topics, but I'm asking a
TECHNICAL question, and NOT continuing the debate on
what is good or bad. If you want to cut to the chase, scroll
down to the last couple paragraphs. On the debate on email,
the only point that I didn't notice was that no one mentioned
the potential conflict/problem of a public, tax supported
agency competing with local for-profit business.  I'm sure that
if any library in Idaho provided free email accounts, etc, that a
number of ISPs would be all over them, in court if necessary. 
Most also missed that there are very basic differences
between public and academic library missions, expectations,
needs, etc.   

Anyway, to the TECHNICAL question and issues for now. 
The unviersity gives free email access to students, from labs,
via easily established accounts on a POP3 server.  No
problem.  The library doesn't provide access to this, as
students can go to any of over 20 labs to do so.  The
university does not provide remote email access to students,
as this has been contracted out to a local ISP who has a
variety of particularly low priced options for them, and is set
up for the support.  Yes, the contract was bid.  

The library restricts access on public workstations to
CDROMs on our network and to a web browser (NS3.02).  All
other things are restricted by the wonderful IKiosk software. 
Library policy says that students may not use chat or email
services in the library, even though they can do so thru web
pages at various sites.   We do not do any filtering at the
moment, and hope not to do so, particularly as related to
content.  On the few occasions I've noted patrons looking at
"adult sites" (for which I didn't need to peer over their
shoulders, as naked people or their various body parts full
screen on a 17 inch monitor are pretty obvious to anyone),
I've suggested to them that though the library and I didn't care
what they looked at and didn't judge them, there had been
cases in campus labs where those who viewed such in a
public area were charged and convicted with sexual
harrassment thru the campus student judicial system.   Sort
of a word to the wise from the older generation.  Some
stopped and some didn't.  Their business, not mine.

On a number of occasions we've asked patrons to leave web
based chat sessions or email sessions when other patrons
were waiting for the web stations.  Few have given us any
trouble when reminded of the signs on the stations forbidding
such.  I'm not a control freak and am rarely in the area....but
the staff who work in reference have asked if there is a way of
blocking access to those web pages.  There is with filters,
but I have some concerns:

Have any of you used filter software for this purpose, to block
sites NOT for content but for "service provided" (e.g. chat
and/or email)?  If so, what have you used and what were your
results.  I'm sure you'd have some problem keeping up with
new chat pages, and maybe with new hotmail-clone
operations.  Are there any other problems?  Have any of the
packages for blocking already dealt with this?  

Since we do NOT want to block content (this is a university,
and as a "pop culture person" who has written and spoken in
that area, I'd be the last to try to judge what research is), has
anyone blocked "services" only?  If so, has that opened you
up to "well, you're already blocking, so just block the content
too" type of argument?  

Again, I don't really want to re-debate the issues of whether
we should or shouldn't do this.  I'm reluctant to do ANY type
of blocking, personally.  But since the top bosses have
asked about doing this, blocking services only, not content, I
need information to feed back to them.

thanks, everybody....

dan