Hibernate files opened with JBoss Tools XML Editor instead of supported Hibernate Editor if opened in Web Projects View.

Create for example Hibernate 3.0 file (Web Projects View->New->File->Hibernate 3.0)
After creation it will be opened in JBoss Tools XML Editor with only one Source tab by default
To open it in Hibernate 3.0 XML Editor need use always "Open with"
If open this file using F3 button or double click on it will be opened in JBoss Tools XML Editor in spite of Hibernate 3.0 XML Editor was selected before.
This situation spread to other Hibernate files created as File->New->Hibernate->