[Boost-users] cannot get graph object deserialized

I am using boost graph library. I need to serialize a graph object and read it out later. But I found my program cant work properly with xml archiver. It always throws exception saying XML start/end tag mismatch - position. I did not define a tag named position in my serialization code. I dont know how to solve it. [Here] (http://www.rapidshare.com.cn/i1cvbXM) is a demo of the problem. Please help me. Thanks!