If we're talking about getting entropy, why don't we go with a better entropy source than the minor disparity between the two calls to time which at MOST will vary by one digit, which is not very entropic.
Why don't you just call hotbits and grab some radioactive decay data in hex format, break it apart and loop over it to give us some real entropy. That WILL decidely minimize the chance of collisions. Since your already acting against data returned by Sys::Hostname, this should be right up the alley of what your doing.