This is an old thread, but it applies to my case.

I've been having the same problems for a while now. It started this past summer (2007) when I noticed that after I'd smoke marajuana I wanted to go pee shortly after and it was hard to pee. Sometimes I'd wet my hands and keep the water running to help me urinate. Went it seemed impossible, I got in the shower and that usually did the trick.

I'd pee a lot. Just like you said. I'd pee tons of urine and I hadn't drank any fluids. One time, I even ran a test on myself. I got out of bed, got rid of my morning urine, and smoked a bowl. I made sure I didn't drink any fluids at all, and it happened. I, as before, peed a lot.

Just like you, I have smoking friends who don't have this issue at all, and it frustrates me for having to go through this every fucking time I smoke.

Did you happen to find anything else about this condition?