Believe it or not, TWiki works just fine running on an IBM 9672 R66 CMOS machine under OS/390 Unix System Services. The biggest problem was getting the file upload function to work (actually turned out to be modifications to CGI.pm) I like the fact that it can run under OS/390 and that it's self contained, nothing else required. I still have some tuning issues to be worked out but I consider the performance quite acceptable.
DanaMitchell
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