BUG #9010: partition by overrides order by in window functions

The following bug has been logged on the website:

Bug reference:      9010
Logged by:          Markella Skempri
Email address:      markella.skempri@onzo.com
PostgreSQL version: 9.3.2
Operating system:   Linux Centos 5.5
Description:

I am trying to get a row_number / rank of a resultset according to a value
that is ordered by date. However whenever I try to use the order by clause,
the partition by clause seems to override the ordering and produce false row
number.

My data:
householdid   previous_day  gap_finish  no_of_gap_days
1    2011-08-15    2011-08-16    1
1    2011-08-16    2011-08-17    1
1    2011-08-17    2011-08-18    1
1    2011-08-18    2011-08-19    1
1    2011-08-19    2011-08-20    1
1    2011-08-20    2011-08-21    1
1    2011-08-21    2011-08-27    6
1    2011-08-27    2011-08-28    1
1    2011-08-28    2011-08-29    1
1    2011-08-29    2011-08-30    1


my query:

select *, row_number() over (partition by no_of_gap_days order by gap_finish
asc) as no_of_Days from temptable;

the results:
householdid   previous_day  gap_finish  no_of_gap_days  no_of_days
1    2011-08-15    2011-08-16    1    1
1    2011-08-16    2011-08-17    1    2
1    2011-08-17    2011-08-18    1    3
1    2011-08-18    2011-08-19    1    4
1    2011-08-19    2011-08-20    1    5
1    2011-08-20    2011-08-21    1    6
1    2011-08-27    2011-08-28    1    7
1    2011-08-28    2011-08-29    1    8
1    2011-08-29    2011-08-30    1    9
1    2011-08-21    2011-08-27    6    1

What I expect to see
householdid   previous_day  gap_finish  no_of_gap_days  no_of_days
1    2011-08-15    2011-08-16    1    1
1    2011-08-16    2011-08-17    1    2
1    2011-08-17    2011-08-18    1    3
1    2011-08-18    2011-08-19    1    4
1    2011-08-19    2011-08-20    1    5
1    2011-08-20    2011-08-21    1    6
1    2011-08-27    2011-08-28    1    7
1    2011-08-21    2011-08-27    6    1
1    2011-08-28    2011-08-29    1    1
1    2011-08-29    2011-08-30    1    2

Thanks for your time