diff -ruB railroad-0.5.0/lib/railroad/app_diagram.rb railroad-0.5.1/lib/railroad/app_diagram.rb
--- railroad-0.5.0/lib/railroad/app_diagram.rb	2009-09-09 09:33:37.000000000 +0200
+++ railroad-0.5.1/lib/railroad/app_diagram.rb	2009-09-09 08:53:58.000000000 +0200
@@ -81,8 +81,10 @@
 
   # Extract class name from filename
   def extract_class_name(filename)
-    #filename.split('/')[2..-1].join('/').split('.').first.camelize
-    # Fixed by patch from ticket #12742
+    filename_array = filename.split('/')
+    filename_array = filename_array[filename_array.index("app").to_i+2..-1]
+    filename_array.join("/").chomp('.rb').camelize
+  rescue Exception
     File.basename(filename).chomp(".rb").camelize
   end
 
diff -ruB railroad-0.5.0/lib/railroad/controllers_diagram.rb railroad-0.5.1/lib/railroad/controllers_diagram.rb
--- railroad-0.5.0/lib/railroad/controllers_diagram.rb	2009-09-09 09:33:37.000000000 +0200
+++ railroad-0.5.1/lib/railroad/controllers_diagram.rb	2009-09-09 08:50:30.000000000 +0200
@@ -19,7 +19,11 @@
   def generate
     STDERR.print "Generating controllers diagram\n" if @options.verbose
 
-    files = Dir.glob("app/controllers/**/*_controller.rb") - @options.exclude
+    if @options.only.blank?
+      files = Dir.glob("app/controllers/**/*_controller.rb") - @options.exclude
+    else
+      files = @options.only
+    end
     files << 'app/controllers/application.rb'
     files.each do |f|
       class_name = extract_class_name(f)
diff -ruB railroad-0.5.0/lib/railroad/models_diagram.rb railroad-0.5.1/lib/railroad/models_diagram.rb
--- railroad-0.5.0/lib/railroad/models_diagram.rb	2009-09-09 09:33:37.000000000 +0200
+++ railroad-0.5.1/lib/railroad/models_diagram.rb	2009-09-09 08:50:16.000000000 +0200
@@ -20,9 +20,13 @@
   # Process model files
   def generate
     STDERR.print "Generating models diagram\n" if @options.verbose
-    files = Dir.glob("app/models/**/*.rb")
-    files += Dir.glob("vendor/plugins/**/app/models/*.rb") if @options.plugins_models    
-    files -= @options.exclude
+    unless @options.only.blank?
+      files = @options.only
+    else
+      files = Dir.glob("app/models/**/*.rb")
+      files += Dir.glob("vendor/plugins/**/app/models/*.rb") if @options.plugins_models    
+      files -= @options.exclude
+    end
     files.each do |f| 
       process_class extract_class_name(f).constantize
     end
diff -ruB railroad-0.5.0/lib/railroad/options_struct.rb railroad-0.5.1/lib/railroad/options_struct.rb
--- railroad-0.5.0/lib/railroad/options_struct.rb	2009-09-09 09:33:37.000000000 +0200
+++ railroad-0.5.1/lib/railroad/options_struct.rb	2009-09-09 08:58:24.000000000 +0200
@@ -14,6 +14,7 @@
   def initialize
     init_options = { :all => false,
                      :brief => false,
+                     :only => nil,
                      :exclude => [],
                      :inheritance => false,
                      :join => false,
@@ -45,6 +46,9 @@
       opts.on("-e", "--exclude file1[,fileN]", Array, "Exclude given files") do |list|
         self.exclude = list
       end
+      opts.on("-I", "--only file1[,fileN]", Array, "Include only given files") do |list|
+        self.only = list
+      end
       opts.on("-i", "--inheritance", "Include inheritance relations") do |i|
         self.inheritance = i
       end