[NTG-context] Texlive2008 and updating context

Hi everyone, I have followed any thread about updating context (on Texlive2008 on ubuntu) and no success yet. After running sudo ctxtools --updatecontext and luatools --generate everything went smooth. But after texexec --make --luatex en I got the following Should I create the cache path /home/mehdi? [yes|no] [no] and after pressing Enter I got fatal error: there is no valid (writable) cache path defined LuaTools | LuaTools | runtime: 69.494 seconds TeXExec | no lua compilations needed TeXExec | TeXExec | tex engine path: /home/mehdi/.texlive2008/texmf-config/web2c/luatex TeXExec | TeXExec | TeXExec | runtime: 70.993183 Thanks.