I can't figure out how it's currently wired, either.
(If you need it, here's a how-to of wiring a 3-way:http://www.hometime.com/projects/howto/electric/pc2el04.htm#three)
See if you can get the electrician to draw a schematic of how it's currently wired and why a jumper would solve the problem.
If you're feeling bold and aren't worried about being electrocuted, use a circuit tester to try to figure out how the wires run - from the panel, from the switches, from the light.
Also, I saw on TV last week a wireless 3-way switch. You hardwire only one of the switches, which acts as a transmitter - the other switch is a wireless receiver. That may be the cheapest option.
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