Vitamin K and boron seriously help. Thanks to those I can go 7 hours without pissing. There's even a theory out there that prostate problems are just a vitamin K deficiency. I get the Super K formula from vitacost.com Previously I was pissing every 2 or 3 hours.
Mucuna extract(contains dopa, relaxes your body)greatly helps as well(if you're willing). DO NOT TAKE BETA SITOSTEROL.
Also, just my own crackpot observation, but niacin(nicotinic acid aka the flushing kind) seems to work somehow as well.