I would suggest that even cutting down the longest poles and using connectors should work out. Maybe drill a couple of holes and run some lag bolts through just to be sure.
A trick I borrowed from some older tent poles has worked well for other PVC projects. I would think it should work here as well.
Drill a hole near the end of each piece to be connected. Then knot some thin bungee cord, string it through the hole in one piece, throught the connecting point, and out the hole in the other piece. Put the pieces together and knot the remaining end so the cord is taut but still loose enough that you can pull the pieces apart.
In addition to helping hold the connection together during use, it will also keep the pieces together as a unit during storage and helps one remember which end of which piece connects where.
Hope that helps. And I hope even more so that I get to put into use some of the great info I'm seeing on this site (I just got here today <g>).