declare
result xmltype;
begin
result := account.get_t(xmltype(
                                  
                                  '<pars><par name=''fls_id''>11811</par>
                                  <par name=''period''>18.07.2012</par>
                                  <par name=''sd''></par><par name=''fd''></par>
                                  <par name=''zayavitel''>289249</par>
                                  <par name=''manList''><val>289249</val><val>289248</val></par>
                                  <par name=''docList''><val sd=''08.09.2006'' num=''880378;880377--сер.77 АА''/></par>
                                  <par name=''currDocZayav''>false</par>
                                  <par name=''jointByFlat''>false</par>
                                  <par name=''onlyCurMan''>false</par>
                                  <par name=''regNo''>б/н</par><par name=''currWithoutDoc''>false</par>
                                  <par name=''flat_id''>1420508</par>
                                  <par name=''house_id''>1365354</par></pars>')
                                  ,64735);                
end;

public String getEGDfromXMLforWService (String xmlType) throws Exception {
    	
    	Connection c = null;
    	CallableStatement st = null;
    	ResultSet rs = null;
        XMLType xml = null;
        XMLType xml2 = null;
        BigDecimal userId = security.getCurrentUserId();
    	
        try {
        	c = Cleaner.getConnection(dataSource, sessionContext,"AccountInfoBean..");
        	st = c.prepareCall("begin ?:=account.get_t(?,?); end;");
        	st.registerOutParameter (1, OracleTypes.OPAQUE,"XMLTYPE");
        	st.setObject(2, xmlType);
        	st.setBigDecimal(3, userId);
        	st.execute(); <-- здесь на выполнение выходит NullPointerException
        	
        	xml = (XMLType) st.getObject(1);
             
        } catch (Exception e) {
        	e.printStackTrace();        	
        } finally {
        	Cleaner.close(c, st, rs);
        }
    	return xml.getStringVal();
    	
    }

        	st = c.prepareCall("begin ?:=account.get_t(?,xmltype(?)); end;");