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The SB-28 should be OK. A handy reference: http://www.botzilla.com/photo/strobeVolts.html found in 15 seconds by Googling "SB-28 trigger voltage"
With regard to using the 580exII on the Nikon body: On a Canon body the flash goes into stand-by "sleep" mode after 90 sec., reawakening when the shutter button half pressed or * / AF-On is pressed (if enabled). To prevent the flash from sleeping in the Nikon you'll need to override that. On the 580ex it is done by holding down the mode button for 2 sec. until the M indicator starts to blink. It may have changed on the 580exII so consult your manual in the section on using it in M mode.