When Enum type (and in some other situations) used in mapping exported doesn't exxport property's type with params. In this situation session factory cannot be built.

It does it in this way:
<property ... type="org.hibernate.type.EnumType">

but must does:

<property ... >
<type name="org.hibernate.type.EnumType">
<param name="enumClass">com.jboss.dvd.seam.MyEnum</param>
...
</type>
</property>

This is connected with JBIDE-4010, so step to reproduce from that issue:
EXECUTE: Import Seam DVD Store Example project
EXECUTE: Open Hibernate Configurations view
EXECUTE: Expand Session Factory
ASSERT: Expanded successfully w/o any exceptions. Classes with @Table annotations should be represented.
EXECUTE: Open Hibernate Code Generation Configurations and create New Configuration
EXECUTE: Select \dvdstore-ejb\ejbModule as Output directory
EXECUTE: Swith to Exporters and select Hibernate XML mappings and Hibernate XML Configuration
EXECUTE: Press Apply and Run button
EXECUTE: Open Hibernate Configurations view
EXECUTE: Edit configuration: Type: Core; Configuration file: \dvdstore-ejb\ejbModule\hibernate.cfg.xml; Property file: empty path. Press Ok button
EXECUTE: Rebuild configuration
ASSERT: Configuration should be rebuilded successfully.
EXECUTE: Expand Session Factory
FAULURE: Problems while creating sessionfactory:
Log attached.