BUG #4514: Pi division error

The following bug has been logged online:

Bug reference:      4514
Logged by:          Traci Sumpter
Email address:      traci.sumpter@opus.com.au
PostgreSQL version: 8.3.3
Operating system:   Linux
Description:        Pi division error
Details:

I am trying to do some calculations within Postgresql and am not getting the
expected result.  the first set proves that the pi works as expected with
multiplication.

Equation   180*pi
VB         565.486677646163
Calculator 565.486677646163
PostgreSQL 565.486677646163
Php        565.48667764616

However if I extend this equation postgres definately fails this test.

Equation   (315-0)/180*pi
VB         5.49778714378213
Calculator 5.497787144
PostgreSQL 3.14159265358979
Php        5.4977871437821

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