ember: handlebars does not satisfy its siblings' peerDependencies

I've just updated ember to 2.4.2:

% ember -v
version: 2.4.2
node: 5.8.0
os: darwin x64

and when I enter: ember init to re run the blueprint as described here: http://ift.tt/1L9IioJ

I get the following error:

 The package handlebars@4.0.5 does not satisfy its siblings' peerDependencies requirements!
Error: The package handlebars@4.0.5 does not satisfy its siblings' peerDependencies requirements!
    at /Users/giulio/Documents/project/node_modules/npm/lib/install.js:125:32
    at /Users/giulio/Documents/project/node_modules/npm/lib/install.js:268:7
    at /Users/giulio/Documents/project/node_modules/npm/node_modules/read-installed/read-installed.js:142:5
    at /Users/giulio/Documents/project/node_modules/npm/node_modules/read-installed/read-installed.js:263:14
    at cb (/Users/giulio/Documents/project/node_modules/npm/node_modules/slide/lib/async-map.js:47:24)
    at /Users/giulio/Documents/project/node_modules/npm/node_modules/read-installed/read-installed.js:263:14
    at cb (/Users/giulio/Documents/project/node_modules/npm/node_modules/slide/lib/async-map.js:47:24)
    at /Users/giulio/Documents/project/node_modules/npm/node_modules/read-installed/read-installed.js:263:14
    at cb (/Users/giulio/Documents/project/node_modules/npm/node_modules/slide/lib/async-map.js:47:24)
    at /Users/giulio/Documents/project/node_modules/npm/node_modules/read-installed/read-installed.js:263:14

The application seems to be working fine anyways, though I need to add ember-cli-mirage addon, and I get the same errors, and the thing is not installed,

I'm not sure which files would be relevant here, as none of the files of my project contains the string handlebars:

% grep -rl handlebars * | cut -d "/" -f 1-2 | sort | uniq
bower_components/ember
dist/assets
node_modules/.bin
node_modules/amdefine
node_modules/async
node_modules/bower
node_modules/broccoli-asset-rewrite
node_modules/broccoli-sri-hash
node_modules/consolidate
node_modules/ember-bootstrap
node_modules/ember-cli
node_modules/ember-cli-broccoli
node_modules/ember-cli-htmlbars
node_modules/ember-cli-htmlbars-inline-precompile
node_modules/ember-cli-preprocess-registry
node_modules/ember-data
node_modules/ember-resolver
node_modules/engine.io
node_modules/grunt-ember-templates
node_modules/handlebars
node_modules/json3
node_modules/mime
node_modules/mime-db
node_modules/mout
node_modules/npm
node_modules/optimist
node_modules/uglify-js