This topic has also lead to heated discussions here based on various levels of understanding of rubber chemistry. Yes, a real "vulcanizing" fluid is better for gluing patches to a bike tube.

However, I have had years of success using Rema patches and plain office supply store Elmer's Rubber Cement to glue them on. I scrub the area around the puncture with the sandpaper in the Rema kit to remove oil or residual mold release from the tube, apply a thin layer of the rubber cement extending a bit beyond where the patch will cover and let it dry for several minutes. Then I remove the foil backing from the patch, apply it over the hole and iron it down with my thumb. Glued on this way I have almost never had one fail or leak.

The beauty of this approach is that the cement comes in a larger bottle, costs little and never goes dry because it's also used for other projects around the house.