diff --git a/lib/thin/runner.rb b/lib/thin/runner.rb
index 1933f8ab..21dab052 100644
--- a/lib/thin/runner.rb
+++ b/lib/thin/runner.rb
@@ -92,7 +92,7 @@ def parser
           opts.separator "Cluster options:"                                             
                                                                                       
           opts.on("-s", "--servers NUM", "Number of servers to start")                  { |num| @options[:servers] = num.to_i }
-          opts.on("-o", "--only NUM", "Send command to only one server of the cluster") { |only| @options[:only] = only }
+          opts.on("-o", "--only NUM", "Send command to only one server of the cluster") { |only| @options[:only] = only.to_i }
           opts.on("-C", "--config FILE", "Load options from config file")               { |file| @options[:config] = file }
           opts.on(      "--all [DIR]", "Send command to each config files in DIR")      { |dir| @options[:all] = dir } if Thin.linux?
         end
diff --git a/spec/runner_spec.rb b/spec/runner_spec.rb
index 844f1335..57328915 100644
--- a/spec/runner_spec.rb
+++ b/spec/runner_spec.rb
@@ -2,10 +2,11 @@
 
 describe Runner do
   it "should parse options" do
-    runner = Runner.new(%w(start --pid test.pid --port 5000))
+    runner = Runner.new(%w(start --pid test.pid --port 5000 -o 3000))
     
     runner.options[:pid].should == 'test.pid'
     runner.options[:port].should == 5000
+    runner.options[:only].should == 3000
   end
   
   it "should parse specified command" do
@@ -164,4 +165,4 @@
     
     runner.run!
   end  
-end
\ No newline at end of file
+end