Oh, yeah, I meant to get back to this, but I was hoping someone with
actual knowledge might respond.

My first question would always be, how much sun is it getting? It may be
getting enough sun to grow happily, but not enough to flower.

The second thing is pruning, here's two links that go into details

http://www.plantamnesty.org/pruning_...t_wisteria.htm

http://www.gardenseeker.com/pruning_wisteria_.htm

and a quote from a 3rd:
"Pruning wisteria extensively during the dormant season may encourage
rampant vegetative growth the next spring. Instead, in July prune out
the long, straggly growth except those branches needed for climbing.
This is more likely than anything else to induce flowering. Shoots
should be cut back one-third to one-half their length. This will induce
them to produce the short spurs that will bear next season's flower
clusters." (from http://www.orchardsedge.com/vines.html)

HTH
Jane