pg_controldata ( some values missing)

Hi,
I wondering about some data missing after the execution of
pg_controldata (pg_control last modified and Time of latest
checkpoint), is it normal ?

pg_control version number: 72
Catalog version number: 200211021
Database cluster state: in production
pg_control last modified:
Current log file ID: 17
Next log file segment: 184
Latest checkpoint location: 11/B6F1C554
Prior checkpoint location: 11/B617B6F4
Latest checkpoint's REDO location: 11/B6BAF378
Latest checkpoint's UNDO location: 0/0
Latest checkpoint's StartUpID: 17
Latest checkpoint's NextXID: 56642758
Latest checkpoint's NextOID: 1648295
Time of latest checkpoint:
Database block size: 8192
Blocks per segment of large relation: 131072
Maximum length of identifiers: 64
Maximum number of function arguments: 32
Date/time type storage: Floating point
Maximum length of locale name: 128
LC_COLLATE: en_US
LC_CTYPE: en_US

#select version();
version
-------------------------------------------------------------
PostgreSQL 7.3.2 on i686-pc-linux-gnu, compiled by GCC 2.96

Ciao
Gaetano