Problems with timezone

​Hello,

I have the following inconsistency in my environment:

postgres@postgres =# SELECT current_timestamp;
              now
-------------------------------
 2015-07-27 16:26:40.001694-03
(1 row)

postgres@postgres =# SELECT blah;
ERROR:  column "blah" does not exist

In my log file:

[2015-07-27 19:27:10.944 GMT] 3397 <postgres postgres [local] 42703>  ERROR:  column "blah" does not exist at character 8
[2015-07-27 19:27:10.944 GMT] 3397 <postgres postgres [local] 42703>  STATEMENT:  SELECT blah;​

My PostgreSQL version is:  9.2.4

cat /etc/issue
CentOS release 6.3 (Final)
Kernel \r on an \m

Could you help me?

Thanks a lot.

Best regards