Looks like section: "ns_section ns/server/${server}" is munged with servers section in config.tcl. Grepping the "enabletclpages" in the log indicates 4 servers defined.. when there should be only 1.
In the line above, "NotFoundResponse" should be your server name. I doubt, that you are using such a strange name, but who knows.
How do you specify the section including enabletclpages? ns_section "ns/server/${server}"? If yes, how do you set the variable "server" in your config-file?