updated README related to type hinting issue

README.markdown

@@ -14,6 +14,18 @@ records being flushed in the behavioral way. List of extensions:
 Currently these extensions support **Yaml** and **Annotation** mapping. Additional mapping drivers
 can be easy implemented using Mapping extension to handle the additional metadata mapping.
 
+## Important
+
+Recently where was a change for type hinting on object manager and other. These changes
+**requires doctrine2 from master branch**. Example:
+
+    git clone git://github.com/doctrine/doctrine2.git myproject/library/doctrine
+    git clone git://github.com/doctrine/common.git myproject/library/doctrine-common
+
+To autoload these libraries use same class loader from doctrine common package for instance.
+    
+If you are using windows, there is **msysgit** tool available.
+
 ### Latest updates
 
 **2011-03-05**