Java core dump free heap size incorrect

Question

One of my Java applications crashed, leading to a core dump.

Java Heap Information 
-Xmx (Maximum Java heap size) : 1368m 
-Xms (Initial Java heap size) : 684m 
-Xscmx (Java class data sharing cache size) : 50M

but the core shows

Free Java heap size: 1.27 GB  
Allocated Java heap size: 1.34 GB

======================
0SECTION       MEMINFO subcomponent dump routine
NULL           =================================
1STHEAPFREE    Bytes of Heap Space Free: 516D2D48 
1STHEAPALLOC   Bytes of Heap Space Allocated: 55800000
=======================

How is it possible that out of the maximum heap size of 1368 m, the size of the free Java heap is 1.27 GB and the size of the Java heap is 1.34 GB.

Object memory segment (reserved) shows 100% usage ie (1368m)