If the first character in a string is '0', then function is_uint_suffix() returns FAIL.
Thus, strings like "0", "01", "0123", "00000" are not recognized as valid unsigned integers.

I think it can be fixed by replacing
if ('\0' == *str || '1' > *str || *str > '9')
with
if ('\0' == *str || '0' > *str || *str > '9')
in is_uint_suffix() implementation in file src/libs/zbxcommon/misc.c.