diff --git a/lib/thor/util.rb b/lib/thor/util.rb
index 110bd9e6..de582366 100644
--- a/lib/thor/util.rb
+++ b/lib/thor/util.rb
@@ -130,9 +130,10 @@ def camel_case(str)
       #
       def find_class_and_command_by_namespace(namespace, fallback = true)
         if namespace.include?(":") # look for a namespaced command
-          pieces  = namespace.split(":")
-          command = pieces.pop
-          klass   = Thor::Util.find_by_namespace(pieces.join(":"))
+          *pieces, command  = namespace.split(":")
+          namespace = pieces.join(":")
+          namespace = "default" if namespace.empty?
+          klass = Thor::Base.subclasses.detect { |klass| klass.namespace == namespace && klass.commands.keys.include?(command) }
         end
         unless klass # look for a Thor::Group with the right name
           klass = Thor::Util.find_by_namespace(namespace)
diff --git a/spec/base_spec.rb b/spec/base_spec.rb
index e5a9561c..2bac020d 100644
--- a/spec/base_spec.rb
+++ b/spec/base_spec.rb
@@ -195,7 +195,7 @@ def hello
       expect(Thor::Base.subclass_files[File.expand_path(thorfile)]).to eq([
         MyScript, MyScript::AnotherScript, MyChildScript, Barn,
         PackageNameScript, Scripts::MyScript, Scripts::MyDefaults,
-        Scripts::ChildDefault, Scripts::Arities
+        Scripts::ChildDefault, Scripts::Arities, Apple, Pear
       ])
     end
 
diff --git a/spec/fixtures/script.thor b/spec/fixtures/script.thor
index f4bca449..eac5d85e 100644
--- a/spec/fixtures/script.thor
+++ b/spec/fixtures/script.thor
@@ -249,3 +249,12 @@ module Scripts
   end
 end
 
+class Apple < Thor
+  namespace :fruits
+  desc 'apple', 'apple'; def apple; end
+end
+
+class Pear < Thor
+  namespace :fruits
+  desc 'pear', 'pear'; def pear; end
+end
diff --git a/spec/util_spec.rb b/spec/util_spec.rb
index 9914706c..80665edc 100644
--- a/spec/util_spec.rb
+++ b/spec/util_spec.rb
@@ -109,6 +109,11 @@ def self.clear_user_home!
     it "falls back on the default namespace class if nothing else matches" do
       expect(Thor::Util.find_class_and_command_by_namespace("test")).to eq([Scripts::MyDefaults, "test"])
     end
+
+    it "returns correct Thor class and the command name when shared namespaces" do
+      expect(Thor::Util.find_class_and_command_by_namespace("fruits:apple")).to eq([Apple, "apple"])
+      expect(Thor::Util.find_class_and_command_by_namespace("fruits:pear")).to eq([Pear, "pear"])
+    end
   end
 
   describe "#thor_classes_in" do