Detailed revision comments:

r6713 | sunny | 2010-02-16 10:12:17 +0200 (Tue, 16 Feb 2010) | 7 lines
branches/zip: Change the bit fields back to ulint. Bit fields were causing
problems with concurrency on SMP systems because of word packing issues.
The number of trx_t's in a system is not sufficient enough to require that
we try and save a few bytes in the data structure.

See rb://255 for details.