Hi sgenevay,
there's one thing that comes to my mind what you could try...
I do not really know how VEP communicates on the network layer, but maybe it's using network broadcasts which might get confused by your network addresses. The '255' (more precisely: all bits set in a given 'rest' field of an IP address) normally is ised as a broadcast address (e.g. to find computers in a network) and as a ground rule this 'address-part' should not be used in normal IP addresses.
To cut a long story short: try to use IP addresses without '255', e.g. 10.254.254.1 and 10.254.254.2. the netmask should remain, for example 255.255.255.0.
That's just guessing and I may be totally wrong with my estimation, but the address change would not make anything worse.
Hth,
/ewo