Why application fails to load Oracle Driver related classes from application in EAP6

Issue

• In EAP 6.2.0 Oracle Driver/Datasource causes issue while aplication tries to load some driver jar classes.
• In a largely stock EAP 6.2.0 installation (using JAR install method) to which the Oracle 11g driver is installed as a module. EAP is running in standalone mode. It is noticed that the OracleDS is bound properly during server startup, but when I try to deploy a particular WAR, the following error is observed:

{
    "outcome" => "failed",
    "failure-description" => {"JBAS014671: Failed services" =>  "jboss.deployment.unit.\"DatabaseWebApp.war\".POST_MODULE" => "org.jboss.msc.service.StartException in service
jboss.deployment.unit.\"DatabaseWebApp.war\".POST_MODULE: JBAS018733: Failed to process phase POST_MODULE of deployment \"DatabaseWebApp.war\"
    Caused by: org.jboss.as.server.deployment.DeploymentUnitProcessingException: JBAS011033: Could not load oracle.jdbc.pool.OracleDataSource referenced in env-entry
    Caused by: java.lang.ClassNotFoundException: oracle.jdbc.pool.OracleDataSource from [Module \"deployment.DatabaseWebApp.war:main\" from Service Module Loader]"}},
    "rolled-back" => true
}
.
.
.

21:27:03,069 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-1) MSC000001: Failed to start service jboss.deployment.unit."DatabaseWebApp.war".POST_MODULE: org.jboss.msc.service.StartException in service jboss.deployment.unit."DatabaseWebApp.war".POST_MODULE: JBAS018733: Failed to process phase POST_MODULE of deployment "DatabaseWebApp.war"
    at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:127) [jboss-as-server-7.3.0.Final-redhat-14.jar:7.3.0.Final-redhat-14]
    at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.4.GA-redhat-1.jar:1.0.4.GA-redhat-1]
    at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.4.GA-redhat-1.jar:1.0.4.GA-redhat-1]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [rt.jar:1.7.0_71]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [rt.jar:1.7.0_71]
    at java.lang.Thread.run(Unknown Source) [rt.jar:1.7.0_71]
Caused by: org.jboss.as.server.deployment.DeploymentUnitProcessingException: JBAS011033: Could not load oracle.jdbc.pool.OracleDataSource referenced in env-entry
    at org.jboss.as.ee.component.deployers.ResourceReferenceProcessor.getResourceRefEntries(ResourceReferenceProcessor.java:159)
    at org.jboss.as.ee.component.deployers.ResourceReferenceProcessor.processDescriptorEntries(ResourceReferenceProcessor.java:73)
    at org.jboss.as.ee.component.deployers.AbstractDeploymentDescriptorBindingsProcessor.deploy(AbstractDeploymentDescriptorBindingsProcessor.java:95)
    at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:120) [jboss-as-server-7.3.0.Final-redhat-14.jar:7.3.0.Final-redhat-14]
    ... 5 more
Caused by: java.lang.ClassNotFoundException: oracle.jdbc.pool.OracleDataSource from [Module "deployment.DatabaseWebApp.war:main" from Service Module Loader]
    at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:197) [jboss-modules.jar:1.3.0.Final-redhat-2]
    at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:443) [jboss-modules.jar:1.3.0.Final-redhat-2]
    at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:431) [jboss-modules.jar:1.3.0.Final-redhat-2]
    at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:373) [jboss-modules.jar:1.3.0.Final-redhat-2]
    at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:118) [jboss-modules.jar:1.3.0.Final-redhat-2]
    at org.jboss.as.ee.component.deployers.ResourceReferenceProcessor.getResourceRefEntries(ResourceReferenceProcessor.java:157)
    ... 8 more

• Why this is happening and how to resolve?