Error reading bookmap dtd

I have a bookmap that contains the following declaration:

I have successfully generated output from this file in the past, however, I created a new project that references this file, and I’m getting the following message:
Fri Apr 15 13:27:28 2011
I1: Starting log for drxml, x002
I1: Opened XML file "C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap"
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
W1: Error reading file http://docs.oasis-open.org/dita/v1.1/OS/dtd/bookmap.dtd, opening
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap
I1: Opened XML file C:\Work\dita\maps\extractor\smartShift_extractor_UG_bk.ditamap… ad infinitum
In addition, the process dcl.exe seemed to be running even after I closed the DITA2Go gui, and my text editor EDIT Plus keeps producing a message saying that the log file is being modified, indicating that some process is still running, trying to update the log, even after I manually terminated dcl.exe.

Any idea what’s going on here?