Problem creating nodes from XML using Feeds/ Feed XPath Parser
Have you tried turning on debugging in the Xpath Parser? It can give you an idea of what is going into the field before any interference like the formatting of the field itself.

I also use Firepath which is an add-on for Firefox for use with Firebug.
I don't use Xpath very often- kind of a quick means to an end- and the two of these tools have been invaluable. Firepath will help you find out if your Xpath is correct.