[Beowulf] Jury rigged ethernet?

[Huntress Gary B NPRI]

This is more than a little off topic but if the answer is encouraging it will strengthen my case to purchase a small-ish cluster significantly.

Basically I am exploring the idea of placing a cluster in a dedicated "non-traditional" physical location where space is at a dramatic premium.  This particular space has existing cabling that I cannot change and it is my only electrical access.  A single existing cable provides 3 phase power, a few DC discrete signal pairs, and a few twisted shielded pairs that were used for serial communication.   The cable is approximately 30 feet long.  I would like to adapt two twisted pairs for ethernet.

What are the chances that I can coax 10Mbps out of this connection with modern (hopefully tolerant) ethernet cards at either end?  Is this doomed to failure?

Thanks,

Gary H.