This almost certainly isn't a real problem but as I was debugging my queries I noticed that space characters in form data are encoded as %20 rather than +
http://stackoverflow.com/questions/1211229/in-a-url-should-spaces-be-encoded-using-20-or
Before I discovered popsicle I was using my own hacked up promised web session code and I ended up using the form-urlencoded package for my encoding. But my decision was based on using the first package I found rather than any careful analysis.