You mean like the ANS 500 running (patched) AIX running classilla.org and floodgap.com? 
Yes, it's 4.1.5, though I hacked it a lot for security reasons. It'll still be in service for awhile longer, though I'm having trouble getting things to compile with the ancient gcc 2 on it (and dynamic linking in that version of AIX is iffy, so everything is statically linked and I freak out the linker every time I do things like rebuild sendmail or named). Still, almost 13 years of service.
Yes, it's 4.1.5, though I hacked it a lot for security reasons. It'll still be in service for awhile longer, though I'm having trouble getting things to compile with the ancient gcc 2 on it (and dynamic linking in that version of AIX is iffy, so everything is statically linked and I freak out the linker every time I do things like rebuild sendmail or named). Still, almost 13 years of service.