EDIT: Still, it would be nice if the right data was placed there, so I'd at least know which real block I am contributing to!
Do you clearly understand what a "share" is and why you are working with difficulty-1 task ?
Just wanted to be sure.
For the record (it's just
now that I notice), it looks like the prev_block hash in work.data is a little-endian series of big-endian 4-byte words:
prev_block: a7741e55 1833dce3 0d9e7e97 a11e5173 d3146037 f0e32a18 00004869 00000000
print: 00000000 00004869 f0e32a18 d3146037 a11e5173 0d9e7e97 1833dce3 a7741e55
I must have been blind.
EDIT: Though, the first 64-byte chunk is indeed ignored, at least by my miner client. It's not necessary for the calculation, since the server gives a ready "midstate".