Tried to install erlang. Got this error message

$ brew install erlang
==> Downloading https://downloads.sf.net/project/machomebrew/Bottles/erlang-R14B04-bottle.tar.gz
######################################################################## 100.0%
==> Pouring erlang-R14B04.bottle.tar.gz
ln: liberts_r.a: Permission denied
Error: The linking step did not complete successfully
The formula built, but is not symlinked into /usr/local
You can try again using `brew link erlang'
==> Summary
/usr/local/Cellar/erlang/R14B04: 6978 files, 261M

Tried the following but did not work

$ brew cleanup erlang; brew unlink erlang; brew link erlang
Removing /usr/local/Cellar/erlang/R14B02...
Removing /usr/local/Cellar/erlang/R14B03...
Unlinking /usr/local/Cellar/erlang/R14B04... Error: Permission denied - /usr/local/lib/erlang/bin/epmd

sudo unlink and link fixed the issue finally