This excerpt taken from the PRXL 8-K filed Oct 27, 2008.
Research and Development
Research costs are charged to the income statement as incurred. Development costs are capitalised if they are attributable to a project that is expected to be commercially viable and of economic value to the business. All other development costs are charged to the income statement as incurred. Development costs capitalised are amortised to the income statement over the expected life of the developed product. Currently all expected lives are 36 months.
Tangible fixed assets used for research and development are depreciated in accordance with the Groups policy.