Type casting bug in 8.1.[67]?

Hello all,

after upgrading from 8.1.5 to 8.1.7, I got errors in the server log when 
updating decimal values using string constants. I tried the same using 
psql (pasted the query from below) and it fails, too. Downgrading to 
8.1.5 resolved the issue.

ERROR:  attribute 4 has wrong type
DETAIL:  Table has type numeric, but query expects numeric.
STATEMENT:  UPDATE reminder SET reminder_charges='0' WHERE reminder_id=29362

reminder_charges is defined as:
reminder_charges       | numeric(5,2)                   | not null

I guess this is a bug.

Best Regards
Michael Paesold