MATLAB: Am I getting inconsistent reports between FEATURE MEMSTATS and MEMORY in MATLAB 7.6 (R2008a)

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The following Tech Note seems to indicate that a matrix can be as large as the "Maximum Free Contiguous Block Size" reported by executing the 'feature memstats'command in MATLAB:
 <http://www.mathworks.com/support/tech-notes/1100/1107.html>
However, this command resulted in the following output on my 64-bit Windows Server 2003 machine:
     Physical Memory (RAM):
         In Use:                             1596 MB (   63ce2000)
         Free:                              31002 MB (  791a63000)
         Total:                             32599 MB (  7f5745000)
     Page File (Swap space):
         In Use:                             1870 MB (   74eaa000)
         Free:                              33887 MB (  845fc5000)
         Total:                             35758 MB (  8bae6f000)
     Virtual Memory (Address Space):
         In Use:                              928 MB (   3a041000)
         Free:                            8387679 MB (7ffc5f9f000)
         Total:                           8388607 MB (7fffffe0000)
     Largest Contiguous Free Blocks:
          1. [at   180401000]             8379758 MB (7fdd6e4f000)
          2. [at    7fff0000]                3072 MB (   c0010000)
 ...
 ans =
   8.7868e+012
However, executing the following command:
A = zeros(2^40,1,'uint8');
results in an "Out of Memory" error.
Further, executing MEMORY results in the following output:
 Maximum possible array:              33885 MB (3.553e+010 bytes) *
 Memory available for all arrays:     33885 MB (3.553e+010 bytes) *
 Memory used by MATLAB:                 331 MB (3.474e+008 bytes)
 Physical Memory (RAM):               32599 MB (3.418e+010 bytes)

Best Answer

The use of FEATURE MEMSTATS to estimate the largest block of contiguous memory is limited to 32-bit Windows platforms as described in the tech note,
http://www.mathworks.com/support/tech-notes/1100/1107.html
On 64-bit platforms, the commands FEATURE MEMSTATS and MEMORY return differing interpretations of available memory.
Executing the following command:
feature memstats
reports the largest memory address block available on the system. This number is in terms of the available memory addresses based on the theoretical limit/process Limit of the architecture (i.e. 32-bit Windows or 64-bit Windows) and not the physical resources that are available.
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