Time difference changed in 7.2 (3rd time post and hoping for the best :)

Hi,

	The difference between two times (interval) seems to have undergone a
change from 7.1 to 7.2. For example 

'1:00'::time - '23:00'::time = @ 2 hours in 7.1 and;
'1:00'::time - '23:00'::time = @ 22 hours ago in 7.2.

I assume there must be some sound reason for this change, but I have
used time differences at loads of places in my considerably large
application and the whole thing goes (not surprisingly) completely
haywire. 

Is there some way I can revert to the old behaviour? Downgrading my
postgres version is not a choice :). IAC, since 

'23:00'::time + '1:00'::interval = '1:00'::time, 

shouldn't the old behaviour be considered the more consistent one?

Thanks for any advice and help. Its critical that I get my application
up and running as quickly as possible. 

Many thanks and regards,
Gurunandan