Redmine

how i can configure 3 decimal places in html output? i enter 0.125 hours and in html output i see 0.13, but when i search month report RM calculate 0.125 hours...
example:
i enter two "spent time" 0.125 hours and 0.25 hours. when i try to see last activities i see two position 0.13 hours and 0.25. if i check summary report i see 0.38. But if i enter 4 position 0.125, 0.125, 0.125, 0.125 i see 4 position 0.13 hours and 0.5 hours in summary report! Thank you for help and sorry for my bad english.