An Error you could check out is the NAT Loopback problem . Here is a link to it , in opensim . There is more information out there about it and how to solve it . Just google Nat Loopback Problem Opensim and you should find out the information . I am not totally sure that this is your specific problem but it sounds like it to me .
Hope the helps http://opensimulator.org/wiki/Viewer Grey Skies Tara -- http://groups.google.com/group/realxtend http://www.realxtend.org