Ways to trip with non-trip weapon?

[Anger Nogar]

Title says it all. Is there a way for my Sohei/Unchained Rogue to trip with his elven branched spear that does not involve taking levels in other classes (basically with feats or gold)?

There was a long discussion if you can trip with a weapon that does not have the trip special ability, but I believe in the end it was decided that you can't.

[Jiggy]

The trip maneuver can always use a weapon. The trip property lets you drop the weapon instead of falling on your ass if you fail by 10 or more.

EDIT: LINK

[Liz Courts]

Duplicate thread, go here.