Hello Hector,
I would like to ask if you were successful with enabling gzip compression on your server.
I've been playing with nszlib in the past couple of days and like you I have been unable to get aolserver 4.5 to server gzip content.
However, I found that if I remove 0-acs-init.tcl and zz-postload.tcl from openacs/tcl/ aolserver ns_zlib works.
I'm guessing that it must be something in acs-init that is overriding ns_zlib.
I'm trying to trace acs-init now with the hopes of pin pointing exactly what is preventing compressed content and I was wondering if you have had any luck.
Thanks,
Hamilton