product option price rounding down to 0 (4 decimal places)

Hi

Please can somebody help me. Im using v1.5.6 and were having problems with the admin - product option pricing. The pricing seems to round to 0, if the cost is 4 decimal places, so for example, if we put in, 0.000499 in the price box, when we click save, the price automatically defaults to 0. Does anybody else have this issue? does anybody know how to stop the price from defaulting to 0.

ive been pulling my hair out for weeks trying to figure this out

i have found a work around. its becuase the mysql table product_option_prices field 'price' is restricted to 15/4 (4 decimal places) Just change field to 15/7 which resolved the issue.