AIX, Hibernate, Java 1.5 website problem

We have an AIX machine running Tomcat 5.0.28 along with Java 1.5. There are two web application on there however when we start Tomcat and unpack the WAR files only one of the sites work. Then if we remove the working site then the other site starts to work. So it appears that one is taking precedence over the other and we just don't know what's going on. Is this a Hibernate thing, AIX memory thing, etc.? We just don't know so if anyone has experienced any problems like this we'd greatly appreciate any feedback.

Thank you!