[NTG-context] ConTeXt installation problem using i-installer(v 2.85)

[Dalyoung Jeong]

Dear all,

Yesterday, I updated ConTeXt using i-installer(V 2.84).
It worked fine with XeTeX too. I am able to make presentation using  
ConTeXt + XeTeX which was not possible before.
Today I tried to update ConTeXt in Mac located in school. At this  
time, I used the upgraded i-installer(V 2.85). But it didn't ask me  
the permission(no Authenticate window). So it couldn't have a write  
permission in the directory /usr/local/teTeX/. I got the warning/ 
error message, "/usr/local/teTeX/share/texmf.local is not writablle.  
I cannot change a nonwritable TeX. Bailing out...".  Hence I couldn't  
install ConTeXt.

What do I have to do to complete the installation?

Thank you.

Dalyoung