Requirement to change Accounting Calendar from period Jan - Dec to Jul-Jun

Hi

The accounting period for the company is 1 January to 31 December. However the year end has now changed from 1 July to 30 June, in line with Government's financial year.

Is there a way to alter the Calendar to this requirement without the an re-implementation of the whole system?

Also if this setup is possible how can we archive it and what will be the impact on other module like Fixed Asset where it uses its own calendar?

Thanks