I'm having a strange issue with DNN 5.6.3

This is happening with 2 websites on 2 different servers, 1 running 2003 and 1 running 2008 R2.  1 is a new site, 1 is a many times updated site.

The issue is that links are being rewritten into bad form.  If I am using the editor (happens with either FCK or Telerik) and select a page or file, it looks correct.  Hit submit and the link removes the subdomain and then is all mangled.  I cannot edit this in the source view, as it is just changed after submit.

Here is an example:
Trying to Link to: http://site1.uoregon.edu/Page1.aspx
DNN rewrites that to: http://.uoregon.edu/Page1.aspx   (drops the site1)

Then in the browser that goes to http://site1.uoregon.edu/Page1.aspx/.uoregon.edu/Page1.aspx

I can actually go into the database and re-add the subdomain to the link and then it will work again, but as soon as i use ANY editor, it will break again.

Can anyone give me some guidance on this, this is obviously a bad bug for us as it completely breaks any new links that are created.