Why is a transaction with outputs of less than ฿0.00005460 rejected?
Anything lower than 5460 satoshis is currently considered dust, that bloats the blockchain, while transferring a value that is lower than what it costs to store the resulting output on disk. From the bitcoinj source:


  Any standard (ie pay-to-address) output smaller than this value (in
  satoshis) will most likely be rejected by the network. This is
  calculated by assuming a standard output will be 34 bytes, and then
  using the formula used in getMinNonDustValue(BigInteger). Currently
  it's 5460 satoshis.