I am having the same issue on DP 8.1. We have been running DP 8.0 for about 10 months and have had zero issues with our VMware Integration. We are backing up VMs from two servers directly, not via vCenter.
Yesterday I upgraded to DP 8.10 and then to DP 8.12.
I got the same System Error: [10054] on both of the VMware Jobs that ran last night.
On the Cell Manager I see application errors when the backup fails.
Faulting application name: vepa_bar.exe, version: 8.10.201.0, time stamp: 0x536c565d
Faulting module name: MSVCP90.dll, version: 9.0.30729.6871, time stamp: 0x4fee5fda
Did you manage to resolve your issue?