A while ago I asked whether anyone had built a working ICQ client in Perl

Have a look at vICQ. Also have a look at the (on that page) mentioned Net::ICQ2000, since I had lots of trouble with Net::ICQ and I think lots of it is attributed to the fact that it uses old, outdated protocols. But I am not sure.

I just think it would be damn useful for server alerts etc...

If you just want server monitors to alert you via ICQ, have them send emails to your-icq-uin@pager.icq.com - I used to monitor web sites this way at my old job. Not that this is much fun compared to hacking your own. :)

is there a shell ICQ client already available that we could pipe stuff to?

Have a look at CenterICQ. I've run this client now and then, and it appears to be very stable and so on. What is useful with it is that you can send events via the command line when it is running, and that you can customize it with external scripts that are run upon rules that you set. There are quite a few examples (just click next at the bottom), of which the one titled Remote control with external actions probably is really interesting to you. :)

There is also mICQ that is a pure command line client, but I haven't tried it.

Hope any of these things help you out.

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