Bracket not working properly

The bracket is not working properly in the logical expression like '(1 == 1) and (2 > 1)'. It is working fine without bracket.

Here is the test case:
public void testCalculate4() {
Map vars = new LinkedHashMap();

String[] testCases =

{ "(1 == 1) and (2 > 1)",// "(1 == 1) and (2 > 1) and (3!=4) and (4!=3)",// "( 2 + 3 > 4 ) and ( 8 - 5 > 2 )",// "(2+3>4) and (8-5>2)",// "1 == 1 and 2 > 1 and (3!=4 and 4!=3)" // }

;

for (String expr : testCases)

{ log.info("Evaluating '" + expr + "': ......"); Object ret = MVEL.eval(expr, vars); log.info("'" + expr + " ' = " + ret.toString()); Assert.assertNotNull(ret); // test in compile mode Serializable compiled = MVEL.compileExpression(expr); ret = MVEL.executeExpression(compiled, vars); log.info("'" + expr + " ' = " + ret.toString()); Assert.assertNotNull(ret); }

}