com.ctc.wstx.exc.WstxValidationException: Unknown reason

i am validating my xml against xsd, if element get null where decimal expected
eg:
xml file:
<price></price>

xsd file:
<xsd:element name="price" type="xsd:float" />

the xmlstremreader getting the below exception and all the remaining elements are treated as erros
com.ctc.wstx.exc.WstxValidationException: Unknown reason
at [row,col,system-id]: [8,14,"file:/D:/workspace/test2/books.xml"]
at com.ctc.wstx.exc.WstxValidationException.create(WstxValidationException.java:49)
at com.ctc.wstx.sr.StreamScanner.reportValidationProblem(StreamScanner.java:540)
at com.ctc.wstx.sr.ValidatingStreamReader.reportValidationProblem(ValidatingStreamReader.java:389)
at com.ctc.wstx.sr.InputElementStack.reportProblem(InputElementStack.java:380)
at com.ctc.wstx.msv.GenericMsvValidator.reportError(GenericMsvValidator.java:538)
at com.ctc.wstx.msv.GenericMsvValidator.reportError(GenericMsvValidator.java:530)
at com.ctc.wstx.msv.GenericMsvValidator.reportError(GenericMsvValidator.java:524)
at com.ctc.wstx.msv.GenericMsvValidator.validateElementEnd(GenericMsvValidator.java:385)
at com.ctc.wstx.sr.NsInputElementStack.validateEndElement(NsInputElementStack.java:410)
at com.ctc.wstx.sr.BasicStreamReader.readEndElem(BasicStreamReader.java:3188)
at com.ctc.wstx.sr.BasicStreamReader.nextFromTree(BasicStreamReader.java:2778)
at com.ctc.wstx.sr.BasicStreamReader.next(BasicStreamReader.java:1054)
at Stax.isValid(Stax.java:104)
at Stax.main(Stax.java:36)