The Safari browser on the iPhone (and version of iPhone) does not support the Javascript method that is envoked when the "Send" or "Post" buttons are pressed on the Glocals Website.
As a result, it is not possible to reply to Glocals messages from an iPhone - only to read them.
This is a real shame in the year 2011, where most people with iPhones (a large market share of an increasing market) spend most of their time browsing social networking sites (if not all websites) on their device on their own time (not work time) rather than from a Mac or PC.
~ Message posted from a PC (first time I've logged in to Glocals on a PC this year)