Yes, you're using the non-threadsafe version of the library. Does the download come with a threadsafe version? If so place it in the relevant subsystem and set the subsystem in the IDE compiler options etc.
I may look like a mule, but I'm not a complete ass.
It's my mistake, I thought I'd posted the source for this ages ago but... nope. So the link in the first post is gone, replaced by a code box and you can tailbite it for yourself if so desired. Threadsafe, Unicode, Mildew Resistant, anything you like.