"godoc" doesnt' work on my system.(I'm using ubuntu 13.04)

godoc fmt

gives the following error

2013/06/08 19:12:43 readTemplate: open /usr/lib/go/lib/godoc/codewalk.html: no such file or directory

"which go" gives:

/usr/bin/go

"go env" gives the following:

GOROOT="/usr/lib/go"
GOBIN=""
GOARCH="386"
GOCHAR="8"
GOOS="linux"
GOEXE=""
GOHOSTARCH="386"
GOHOSTOS="linux"
GOTOOLDIR="/usr/lib/go/pkg/tool/linux_386"
GOGCCFLAGS="-g -O2 -fPIC -m32 -pthread"
CGO_ENABLED="1"

What should I do to make it work?

ubuntu go environment-variables
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