This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
Making that method synchronized will only work if there's only a single instance of the class that contains the method. If there are several instances then the code needs to synchronize on the same object for all instances - maybe the Class object of that class.