JsonSlurper in 2.4 loses precision of big integers truncating them to longs

Consider the following json string:

 

{"x":11819408672106971000}

 

When parsed by a JsonSlurper x value is trimmed to a -6627335401602580616 as a result of the Long overflow.

The reason for this is the following code in the CharScanner.java starting from line 660:

 

final int length = index - from;

if (!foundDot && simple) {
  if (isInteger(buffer, from, length)) {
    value = parseIntFromTo(buffer, from, index);
  } else {
    value = parseLongFromTo(buffer, from, index);
     }
} else {
  value = parseBigDecimal(buffer, from, length);
}

Basically all the numbers besides ones in the scientific notation or containing dots are treated as long at best.