insufficient precision may result in incorrect data

our current database schema is limited to 4 decimal places for decimal values ("float" type). in some cases this can result in incorrect data.
for example, icmppingsec documentation says "If host is not available (timeout reached), the item will return 0."

if we ping a low latency host (localhost being the easiest example), results from fping might be :

127.0.0.1 : [0], 84 bytes, 0.04 ms (0.04 avg, 0% loss)
127.0.0.1 : [1], 84 bytes, 0.04 ms (0.04 avg, 0% loss)
127.0.0.1 : [2], 84 bytes, 0.04 ms (0.04 avg, 0% loss)

127.0.0.1 : [0], 84 bytes, 0.04 ms (0.04 avg, 0% loss)
127.0.0.1 : [1], 84 bytes, 0.03 ms (0.03 avg, 0% loss)
127.0.0.1 : [2], 84 bytes, 0.06 ms (0.04 avg, 0% loss)

in both cases average would be below 0.05.

zabbix stores these values as seconds, and with decimal places limited to 4... we get all zeroes - which was supposed to indicate connection problems.