I got the exact error as you:
Failed to read schema document 'orm_2_0.xsd', because 1) could not find the document; 2) the document could not be read; 3) the root element of the document is not <xsd:schema>.
I searched for the key word, and this page is the only one referring this error.
It turned out that it is caused by jar conflict. For my case, there are both hibernate3 and hibernate 4 on classpath. Hope it helps.