Okay, so I've been dealing with this BS for a day or two now.
My particular situation seems to involve this, from vmware-converter-worker-1.log
2013-09-08T16:45:04.953-04:00 [04564 info 'Default'] Disk signature found 1101734678, disk size in sectors 314693632, sector size 512
2013-09-08T16:45:04.953-04:00 [04564 info 'Default'] Partition found type Unknown(222) name:Unknown start:2048 size:112640 primary
2013-09-08T16:45:04.953-04:00 [04564 info 'Default'] Partition found type HPFS/NTFS(7) name:HPFS/NTFS start:114688 size:314572800 active primary
2013-09-08T16:45:04.953-04:00 [04564 info 'Default'] Disk with signature 1101734678, recognized partitions 2
Here's the problem. The original partition table (and physical disk) has partition 1 starting at the 64th sector (sector 63), not the 2049th sector (sector 2048) and ending at sector 112454 (the 112455th sector), giving an implied size of 112454 - (63 -1) = 112392 sectors. This is the dell utility partition (type 222=0xDE), and this is the way it came from the factory.
The "cylinder" size implied by the way Dell partitioned the disk is 63 sectors per cylinder (e.g. 112392 = 63 * 1784 [exact]). However, using fdisk from sysreccd, removing the partitions (without writing and saving) and adding partition 1 back gives a choice for the (default) starting point of the partition as sector 2048, and any earlier sector is disallowed.
One surmises that Converter tried to make the virtual partition table the same way, but then failed to adjust the size and position of the new virtual partitions to reflect the new "implied" cylinder size of 2048 sectors. E.g., 114688 = 56 x 2048 (exact). Will look at the underlying data...