The "Administration And Configuration Guide" (http://www.redhat.com/docs/en-US/JBoss_Enterprise_Application_Platform/5.0.0/html/Administration_And_Configuration_Guide/Configuring_JDBC_DataSources.html) indicates that the JDBC datasource blocking-timeout-millis default value is 5000ms. However, the true default value is 30000ms.

This can be verified by looking at http://anonsvn.jboss.org/repos/jbossas/tags/JBPAPP_5_0_0_GA/connector/src/resources/stylesheets/ConnectionFactoryTemplate.xsl which sets the default values when they aren't present in the *-ds.xml file.