isExe only returns true when everyone has execute on the binary.

[Alex Crowe]

Command returns not found when everyone doesn't have execute

eg:

-rwxr-x--- 1 root webapps     463 Dec 13 12:18 compass
$ node node_modules/.bin/which compass
not found: compass
$ chmod 755 compass
$ node node_modules/.bin/which compass
/usr/local/bin/compass

version: 1.0.5
os: debian wheezy

[isaacs]

This works fine for me. Are you perhaps not in the webapps group, or not the root user?