The e-commerce web sites receive a great and varied number of visitors every day. These visitors share the application server?s limited resources and when there are too many clients connecting to the web site, it is possible that they hinder between them, even to overload the application server. These visitors can be divided in different categories, depending on their importance from site viewpoint. Considering the importance that in these web sites some client connections (e.g. buyers? connections) finish successfully before other connections, in this paper we propose a mechanism to provide different quality of service to the different client categories by assigning different priorities to the threads attending the connections. After observing that Java Thread Priorities are only applied within the JVM, and moreover, these priorities do not reach the O.S. threads, we propose to schedule threads using the Linux Real Time priorities. Our results demonstrate that different quality of service classes can be supported using this mechanism.