Hello,
With v1.1.5.1 on linux:
reloading the blockchain with the bootstrap or not: a lot of
  getblocks stopping at limit xxxxxxxx xxxxxxxxxxx
received block xxxxxxxxxxxxxxxxxxxxxx
ERROR: CheckProofOfStake (): INFO: read txPrev failed
and
ERROR: CheckProofOfStake (): INFO: check kernel failed on coinstake
and
WARNING: ProcessBlock (): check proof-of-stake failed for block

From the block:
Rescanning last 1377571 blocks (from block 0) ...
An explanation?