[NTG-context] ConTeXt Live not working

Trying to typeset the default ConTeXt Live \starttext Hello world! \stoptext I get the following message: TeXExec | processing document 'texweb.tex' TeXExec | no ctx file found TeXExec | tex processing method: context TeXExec | TeX run 1 TeXExec | writing option file texweb.top TeXExec | using randomseed 884 TeXExec | tex engine: pdftex TeXExec | tex format: cont-en This is pdfTeXk, Version 3.141592-1.40.3 (Web2C 7.5.6) %&-line parsing enabled. (/opt/context/current/texmf/web2c/natural.tcx) I can't find the format file `cont-en.fmt'! TeXExec | runtime: 0.776454 It seems that it doesn't work. It happens also with XeTeX and LuaTeX. Pablo