BUG #8067: now() bug?

The following bug has been logged on the website:

Bug reference: 8067
Logged by: Istvan Kassai
Email address: kako(at)zhnet(dot)hu
PostgreSQL version: 9.0.1
Operating system: Linux DRONE 2.6.32.27 #5 Wed Dec 21 12:11:46 CET 2
Description:

function "now()" sometimes returns with a value with timezone data,
sometimes without.

for example:

*****************************************
therm=# select now();
now
----------------------------
2013-04-14 06:58:12.056065
(1 row)

therm=# select now();
now
-------------------------------
2013-04-14 08:58:12.766165+02
(1 row)

therm=# select now();
now
----------------------------
2013-04-14 06:58:16.046629
(1 row)
*****************************************

is it a bug or a feature?