Basically having following class in your deployment:

public class BeanDefault<T extends AbstractClass> {}

and its speciliazation like this:

@Specializes
public class BeanCustom<T extends AbstractClass> extends BeanDefault<T> {}

You get following exception (which is IMHO inappropriate) during Weld boot time:

org.jboss.weld.exceptions.DefinitionException: WELD-001511 Specializing bean Managed Bean [class mypackage.BeanCustom] with qualifiers [@Any @Default] does not have bean type class mypackage.BeanDefault<T> of specialized bean Managed Bean [class mypackage.BeanDefault] with qualifiers [@Any @Default]
	at org.jboss.weld.bean.AbstractBean.postSpecialize(AbstractBean.java:287)
	at org.jboss.weld.bean.AbstractBean.initialize(AbstractBean.java:124)
	at org.jboss.weld.bean.AbstractClassBean.initialize(AbstractClassBean.java:175)
	at org.jboss.weld.bean.ManagedBean.initialize(ManagedBean.java:329)
	at org.jboss.weld.bootstrap.AbstractBeanDeployer.deploy(AbstractBeanDeployer.java:117)
	at org.jboss.weld.bootstrap.BeanDeployment.deployBeans(BeanDeployment.java:217)
	at org.jboss.weld.bootstrap.WeldBootstrap.deployBeans(WeldBootstrap.java:357)
	at org.jboss.as.weld.WeldStartService.start(WeldStartService.java:63)
	at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1980) [jboss-msc-1.1.5.Final-redhat-1.jar:1.1.5.Final-redhat-1]
	at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1913) [jboss-msc-1.1.5.Final-redhat-1.jar:1.1.5.Final-redhat-1]

It manifest with following exception in versions prior to EAP 6.3.0 (Weld 1.1.19.Final):

Caused by: org.jboss.weld.exceptions.DefinitionException: Exception message for key SPECIALIZING_BEAN_MISSING_SPECIALIZED_TYPE not found due to Can't find resource for bundle ch.qos.cal10n.util.CAL10NResourceBundle, key SPECIALIZING_BEAN_MISSING_SPECIALIZED_TYPE
	at org.jboss.weld.bean.AbstractBean.postSpecialize(AbstractBean.java:287)
	at org.jboss.weld.bean.AbstractBean.initialize(AbstractBean.java:124)
	at org.jboss.weld.bean.AbstractClassBean.initialize(AbstractClassBean.java:175)
	at org.jboss.weld.bean.ManagedBean.initialize(ManagedBean.java:329)
	at org.jboss.weld.bootstrap.AbstractBeanDeployer.deploy(AbstractBeanDeployer.java:117)
	at org.jboss.weld.bootstrap.BeanDeployment.deployBeans(BeanDeployment.java:217)
	at org.jboss.weld.bootstrap.WeldBootstrap.deployBeans(WeldBootstrap.java:357)
	at org.jboss.as.weld.WeldStartService.start(WeldStartService.java:63)
	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]